Quite a balanced view Roger. Most older housing stock remaining in London was built without damp-proof courses or cavity walls and in the main stays remarkably dry. But ground levels have risen after various owners lay yet another layer of paving over old, until outside paving is level with inside floors. Walls are rendered and painted instead of being left to breathe. Chimneys blocked up and plastic windows installed. Overoccupation of ever decreasing sized properties then pours water vapour into what has effectively become a plastic bag. Cooking on gas releases even more water vapour. Result is condensation, as you described so well, on the colder surfaces. The rising damp myth a book by Jeff Howell the building science lecturer does put a big hole in the damp proofing industry but the RICS are equally to blame for allowing their surveyors to hide behind their damp meters most of whom have no idea of their serious limitations.
I think the problem was with the rising damp industry is they were a lot of scam artists that attributed all damp as rising damp and charged thousands to solve a problem that wasn't there. It was condensation or penetrating damp, especially in old building where the outside ground level had built up above the hard brick course or above vents.
@@SkillBuilder There are people that go too far on both sides, those that believe moisture cannot go up a wall under any circumstances and those that believe it can wick up a brick or even a stone. And both sides are as stuck in their ways as flat earth folk are. All I know is I took all the cement pointing off my wet 3ft thick sandstone wall (built 1685) and water came out of it for a week. Lime pointed it and it's bone dry inside and out now, BUT ... I reckon it needs the log burner in the hearth to keep it that way.
@@phoenixdundee Exactly what he says, water is no longer trapped and evaporates into your house but it still goes up the wall. Question is what happens on the inside? I suppose more ventilation and higher heating costs?
@@SkillBuilder In my view Rising damp its not a myth its a Fact , just ask any flat owner who has a basement flat for a while he can comfirm and tell storys :) not pleasent ones , been working with surveyors and flat owners for last 12 years around London and on basement flat happens a lot . Im not a builder but i was wroking close with contractors and surveyors from start until the project end can say its not a myth . All the best Roger
I have a customer with a small mould issue, no trickle vents, clothes dried on radiators , north facing gable with cracked render, etc etc. Gave the customer some advice, but he opted for getting a plasterer in who hacked off the first metre and then reinstated it, a practice synonymous with rising damp. Only issue is it’s a second floor flat!
I've seen damp getting through about 40cm of wall laterally when the outside render was cracked, and these were very small/hairline cracks. The wind also helps drive it in I think.
@@stonemasonlew9349 it’s a solid brick built gable with a cement render. The render is cracked and north facing. My point was that the damp would have had to jump from the ground floor onto the second floor therefore making the plaster/render hack off a waste of time!
@@thesunreport agreed, the 3 story Victorian building is on the coast, so driving rain is definitely an issue. I had suggested repairing the cracks in the render and then coating with storm guard or a similar product, more adequate ventilation, the cessation of clothes being dried on rads and so on and so on. The decision to hack off and re render/ plaster is a waste of time as I’ve never known rising damp to jump from a ground floor to a second floor!
I don't think anyone really believes that rising damp is a myth do they? It's just that 90% of damp cases are not rising damp. I've even seen cases where there is a perfectly good original slate damp proof course and some damp roof cowboy has drilled holes all above it to 'treat'. And of course it didn't fix the issue because it was a high ground level and breathability issue
As a Building Surveyor, I don't think I've ever met any qualified surveyors who would argue that rising damp doesn't exist at all, just lots who (I would say rightly) believe that the cause of the damp is usually more likely to be something else.... i.e penetrating damp from the exterior, raised exterior ground levels, poor ventilation of underfloor voids, poor choice of plaster/render material, condensation etc etc. The chemical DPC industry is still a bit of a racket, in my view. I have never specified one, though I would never rule it out completely, i'd just want to try lots of other things first! Some of the confusion comes, I believe from some research which was done some years ago at London South Bank University, where they were not able to recreate rising damp in lab conditions. Clearly, lab conditions are not necessarily indicative of the real world, and I took the outcome of the research to be that water moving upwards via capillary action is simply a lot less common than some people think.
I wish people would replace the words "RIsing Damp" with "TRAPPED MOISTURE". They their brains would be focussed a little better. Capillary action is real. Solid walled buildings are real. Moisture travels from the ground to escape outwards UNLESS its trapped by cements /plasters etc etc THis guy has done himself no favoure. Just comes across as a rather thick, ranting builder! The sort that we earn good money from undoing all their non-working solutions.
@ Numero uno: Maybe because it is necessary to have a DPC ...It is a modern way of building using cement and modern brick, for speed and cost etc (but don’t forget all the houses (cavity) that have their internal and external walls ‘connected’ by poor workmanship (cement droppings bridging etc) and what do you get apart from huge repair bills ? Damp walls or wet walls STILL ! (Even with a DPC !) Some would say rising damp ! Then presumably charge a fortune to ‘waterproof’ inside or outside and or damp injections etc etc further reducing evaporation...You have to be careful ..Cement is a huge polluter of CO2..global warming ! many old buildings were fine and dry until modern materials (cement) were used to repair..leading to “so called Rising Damp ‘...Majority of housing stock does not have cavity walls traditionally, so you need to head back to ventilation humidity breathability for those... Cavity walls a fine modern initiative, (except for the pollution/warming etc) and still suffer condensation ! SO...maybe extra jumper in winter..Can’t have yr cake and eat it !? 3:29
There is no confusion and you don’t need a lab to recreate rising damp. Simply put a brick in 5mm of water and leave it there. You will physically see it rising!!!! Flat earthers!
I've renovated a few houses now and had to remove bricks behind skirting to access the cavity to scrape out cement snots. Worse on houses built 100 years ago with lime as some of the lime crumbles down over time. I then attatach a length of waste pipe to a Henry vacume cleaner and suck it all out.
Buildings need to breath because of the condensation caused by people living in it. Trapped condensation - trapped by modern "damp proofing" methods. It's almost always never actual rising damp, that's the reason given for expensive remediation work.
I'm a rocket scientist, and I've been to space and I can tell you rising damp is a myth. It's actually aliens pissing against your house at night... and the earth it flat 🤣🤣🤣🤣🤣🤣🤣🤣
20 years ago, we were on holiday in Florida at a fast food outlet. It was October, the outside temperature was around 85 deg F (30 deg C), the restaurant was air conditioned. What I remember seeing was massive condensation at the non double glazed windows, caused by the temperature inside the restaurant (around 66 to 68 deg F, 19 to 20 deg C) meeting the hotter air outside.
Bought my house (1930’s three bed terrace) about 9 years ago. Was told by surveyor that it had rising damp (rotten floors, damp walls ect) On closer inspection the exterior ground levels had risen above the damp proof course Took ground levels back down fixed all damage caused problem solved 👍
So the surveryone was rihgt to say it had rising damp but did not show the cause. This is often the problemm they simply say to get it diagnosed which often means another surveryor/salesman. That is the disconnect.
Britain’s expert and guru on damp In buildings is Pete at Heritage House Building and Restoration. He’s an RICS conservation surveyor. I recommend reading their website and watching the videos. It’s eye-opening and very informative. He should be given an award for his relentless exposure of unnecessary remedial works and the real causes of damp. Actually, he doesn’t really believe in rising damp! And incidentally, why show Venice as proof of rising damp? It’s built on water! Most British Homes at worst, would sit on slightly damp soil for part of the year.
Just to be clear. Pete is not an RICS accredited conservation surveyor and I hope he is not claiming that. He doesn't hold any notable UK professional construction qualifications and his views are not particularly expert or revealing. Misdiagnosis and application of inappropriate remedies by unqualified people in the damp and conservation sector is by far the most common problem leading to manifest damp penetration. Venice is a classic example of the physics of how water can move through building materials including rising from below and has been a factor known of for centuries.
Knowledge is king, and Roger have more than his fair share of it bless him . The first house I ever bought I did a silicone injection system , which I did my self , it tuck me about 3 days to complete . At the time a lot of companies would have done it in half a day , because they didn’t allow enough time for the silicone to penetrate into the bricks . So it was a totally waste of time , knowing this a pumped as much as I could in till I saw it coming back out of the bricks and mortar . Well that was some 40 years ago now so it would be interesting to see if my efforts payed off in the long run . Thanks again Roger for your tieless work in bringing this to everyone’s attention, because silly statements like your describing could cause a lot of problems for people. Best wishes and kind regards as always 😀👍👍👍
Really what most of the people saying rising damp doesn't exist mean that it isn't the main cause. Most people know that when you get called out to a damp issue if it isn't a basement it's going to be landscapers that just completely ignore the dpc and air bricks (yes the brickies point of veiw 😂). And if it isn't that there's leaking guttering or drain. But rising damp actually being the main issue isn't it most of the time, yes the injection damp proofing is probably going to be the most cost effective way after you've spent a few k on getting your new paving.
What a reasoned argument you give Roger, scientific, balanced & not biased or ranting in any way. BTW: a) how much damp do the Dutch suffer? b) Who says damp cannot rise? it can but not in masonry, it is when the cement is bridged by porus materials such as plaster or a render which creates a capilliary gap..
Interesting rant on Rising Damp. You are right, on many levels, including that condensation is commonly misdiagnosed as rising damp. And that a DPC is useful for stopping water rising-up a porous brick. What many people don’t understand is: 1. Rising Damp is defined as the rise of moisture from groundwater. 2. Groundwater being water under the water table. 3. Rainwater in contact with a wall may result in rising damp like symptoms but unlike groundwater, rainwater in soil, can and should be removed through improved drainage. 4. The rise from rainwater in soil is considerably smaller than from rising damp as the soil is unsaturated and therefore water will mainly be drawn down, not up. 5. Like rainwater and groundwater, water from any source can be absorbed up a porous brick, including condensation of a solid floor. 6. Condensation within a wall causes heat loss increasing the risk of condensation. Gravity drawn moisture down and the base of a wall is normally the coldest part of a wall. So condensation is most commonly found at the base of a wall. It expands upwards as condensation increases, for that reason condensation in a wall often appears to rise, leading to condensation commonly being misdiagnosed as rising damp. 7. Chemicals and damp proofers slurry may hide condensation or water from defective gutters etc. for a while, but unless the root cause is dealt with, the moisture will eventually show through. Interestingly no wall suffering from rising damp has been preserved so that it can be studied and learned from. There was an attempt a few years ago, but the wall dried out when it was covered.
I agree with the points you make but I would suggest that the University of Bolgna has many examples of rising damp and carries out trials in many historic buildings
Been to a few jobs (usually let properties) where they've claimed it was damp all of the time. Turned out the first metre of roof felt was knackered and rain was trickling down the cavity.
As you rightly say, in older buildings, clear out the cavities where snotts over the years have fallen and built up over the DPC level, especially where lime mortar was used in construction, and make sure that exterior ground levels are 6" below DPC, old buildings need to breathe!
Ah you're brilliant. Love your work. I've seen a mock danger sign "translated" from Japanese: "Danger: do not dumb here. Dumb free area." You need one for your shed or whatever.
Excelland and justified rant Roger ! Damp in buildings is a complex issue and like you say many people are not aware of why it is happening. Most people don't have a clue about how much water is released into the air inside the building each day. Moisture given off by the people living in the building, washing drying, showers, baths etc. Gallons of water floating about in the air which In the hemetically sealed buildings we have to day has got to go somewhere. There's little to no ventilation to the outside to carry it out. It will find cold spots in the building and condense and then black mold will eventually appear and the panic sets in then ! And yes, rising damp does occur - but to different amounts in different materials. Semi-engineering bricks an fresh mortar are usually pretty good at preventing rising damp as are dense blocks. But once the building gets older the mortar starts to break down and that is when it loses its water resistance and damp will start to travel up the mortar joints. The amount of times I have seen perfectly good blue bricks in old buildings that have been drilled into and chemical injection supposedly injectedinto them !! Totally ignoring the cause of the problem which is the mortar in the joints that's failed..
You sorted my head out of fear 😊. I am moving to my last home in my senior years with little funds. You are teaching really helpful information. I will have a go at fixing my damp bungalow. Thank you for helping me out. Love the way you present your advise. Great channel.🙏
Cracking rant! We had rising damp in our old utility room- the walls were literally damp to touch when we moved in. DPC was being bridged by some badly laid concrete. Cut out the edges, and left a gap between the slab and the building. Left the plaster as we knew the room was going tk be replaced. Dried out within weeks and stayed bone dry for 4 years until I knocked it down.
On the subject of DPCs you have to understand they date back to a time when buildings were put up using hand mixed porous lime mortar and a huge variety of vernacular materials of varying properties and quality. They make little sense in modern buildings built using OPC and hard fired bricks, yet modern builders seem to be obsessed with them. There is a long standing idea that British houses are built in swamps with only a thin strip of plastic between warm dry comfort and crumbling soggy walls. If the ground is wet then people need to find out why and not just squirt some chemicals into the walls. With damp you have to fix the cause and not the symptom.
I'm only 1.5 minutes into your vid Rodger and already I know that you are correct. I'm from England and now live in the balkans, Bulgaria. It's a range of mountains that weave through europe like a snake. I have a two storey house, downstairs is natural stone and upstairs is homemade or village made brick. I am surrounded by mountains and I can watch the clouds being made and rising from the earth from my window, when this happens the temperature drops in my house and I can feel the damp coming up from the earth. I live upstairs only, downstairs is great for storing food and making wine, it has a temperature that is more stable. In the summer it can reach 42c upstairs and remain 25 downstairs. I would say that rising damp is natural, it's the mold that's unnatural because of the lack of ventilation. always keep your home ventilated and most of the problems will disappear. Thanks Rodger.
I agree completely, problem is when these companies turn up and sell you a damp proof system after using a silly meter on your walls. These damp proof systems cost thousands and in reality you probably just need to redecorate or open a window in the majority of cases, my house being one of them. We purchased a house that our surveyor said needed a full damp proof system installed, cost the previous owner 14k before we could buy it. It now has a stupid layer of concrete on the lower half of the walls that does absolutely nothing other than potentially caus damp issues itself. After spending 3 years renovating the house and seeing the condition of the brickwork, it has no signs of damp anywhere, bricks are bone dry. In this country also, mortgage companies listen to surveyors whenever damp is mentioned and demand a damp proof system be installed before it can be sold. The industry is all wrong and needs sorting out, sooner rather than later.
@ matte : I agree whole heartedly (as I fell foul of that system many years back-and it too failed after a few short years..) Old stone wall etc BUT concreted and DPC floating floor done many moons ago unfortunately 3:38 .. So soil damp rising still rising through walls causing salt damage etc.. Nobody living there now therefore cold ish and needs time to dry out and breathe plus normal heating ..Hopefully it will get better...But those damn Floors ..too expensive to renew with limecrete breathing type floor and physically beyond me now..
I’d like to see a video about the most common building control fails, or maybe some of the more obscure regs that people miss. I’m surprised building inspectors aren’t more stringent with keeping the cavity clear
Your last sentence, I couldn't agree more with. I imagine it's difficult to police, or time issues on getting it inspected (does somebody have to inspect it before the roof/joists start going up?).
@@lloyd4011 they don’t inspect before joists. They’ll usually pay a ten minute visit once the structure is built before insulation but as the cavity is usually full of insulation, wouldn’t be able to see the the damp course to check it’s not bridged.
As a building surveyor for over 40 years I did 15 inspections a day for 4 days a week 1 day writing reports. Of those average 15 inspections three quarters would be to inspect rising damp lets say 10 inspections for rising damp of those inspections only 1% would be water penetration. The test used is one that is accepted by the courts or arbiter A discreet hole is bored in the affending section of wall and the colour of the dust is registered ie if the dust becomes lighter it is condensation. If the dost becomes darker it is water penetration. If it went darker it is water penetration. The then would be weighed and then subjected to a gas pressure vacuum and the dust re weighed establishing a penetration ratio the water is tested 1st for chlorine if present it is domestic water, then for glycerene which shows it is from a leaking central heating system then it is tested for traces of effluent which would indicate a broken drain. We are advised not to use the term rising damp as this implies water traveling vertically. Water is very heavy and for it to go vertical it must be pumped. There is an argument it can be drawn by capillary attraction so is it through the brick is the brick a soft porus brick or is it travelling through the joints? At Building college built dwarf walls using different bricks bult in galvanised trays never observed water travelling upwards except when more water was put in the tray. Seen plenty of water penetration usually poor cavity trays, parapet walls. Most of my work was by the Thames some of the structures 2, 3 maybe 4 hundred years old Sam Pepys office at the old Deptford Navel yard comes to mind, no damp course, snuff dry. Of Course the well built survives the dross goes into history. I think water penetration is a better word Rising Damp is a television programme. Good rant though.
@@jeffhenderson9595 If the inspection is condensation and in most cases it is observed instantly it is down to life style they would receive a very comprehensive booklet or I would arrange one in what ever language they required. As it is social housing the visits would be selected close together. We tried to work an 8 hour day which gives 1/2 an hour per visit though allegedly we were on flexi time. We were issued with mobile phones so we could inform the resident how we were doing. The call center only confirmed am or pm appointments. As Local Authority employees over a certain grade we were expected to attend evening meetings some council meetings. some tenants asociation meetings sometime because the resident worked shifts an evening visit was arranged. The call center would arrange the appointments and log the description as stated by the resident which would be rising damp
That was a fine rant tonight Roger 😃. What about the surveyors for mortgage companies that used to say virtually every house need a damp proof course installing, I’m sure often it was condensation or damp caused by other things such as faulty fall pipes etc. Not bought or sold a house for many years but remember all those surveys well from the 80s and 90s. It’s just the rich tapestry of life.
If there's no such thing as rising damp, how about 'falling damp?' That's usually caused by leaking roofs or faulty plumbing. Using a meter, rising damp can be detected in walls quite easily. Love the botany lesson, Roger. David Attenborough, watch out. Very informative post as an analytical chemist myself, now retired, the use of silicone fluid to help damproofing courses more effective still interests me. My house is a 90 year old 3 bed semi, built with Accrington brick, one live chimney and central heating. There are now issues with rising damp 40 years after the DPC was done, time to call in the experts for a survey.
Put the tip of a towel in some water and watch what happens! Simple. However I assume most people get confused as a lot of damp problems in houses is either poor guttering and drainage or sweating inside
Fabulous thumbnail picture for this video. The last time I saw that expression deployed to such great effect was by Kenneth Williams. The subtitle should be “Ooh, I have never been so…”
Also of damp issues are also to do with showers in every home, they create a lot of vapor and it settles on cold walls so if you have a cold home it stays
I was under the impression that damp would only rise about 30 inches ? That's what we were told at college. I saw a documentary several years ago. It was made by a chap who goes around doing inspections on houses for house buyers. He said that in all of the inspections of damp he had done over many years, they were rarely caused by a faulty damp course. there are many ways as to how moisture can penetrate a building. Ground level, faulty RWP's etc.
The idea that rising damp won't go above one metre is false. There are lots of examples of it going above that but if it is allowed to evaporate then is will do so in the first metre.
Excellent rant Roger and totally correct! I did work for a remedial treatment company in the early 90’s. In hindsight I only found one case of ‘real rising damp’ where the damp had risen to approx 900mm which was in an old empty house, quite fascinating to behold if I’m honest, it was a textbook case. The ‘failure of the damp proof course’ is in the main a myth in my experience. The main cause of damp in properties is down to many issues; condensation, blocked cavities, hygroscopic salts, penetrating damp where walls are solid, and one of the worst in my experience ‘sulphur salts’ caused by penetrating damp down a chimney where no cowls have been fitted and the chimney is no longer in use as an open fire place. In my experience chimney breasts do not have a dpc and once decommissioned as an open fire tend to suffer with rising damp as well as penetrating damp where rain can get down the flue and they are not vented. If used as a flue for a gas fire, this is further exacerbated as gas is a ‘damp heat’. The end result is yellowing damp patches on and around the fire place. If you have solid walls and suffer with penetrating damp then I would recommend ‘Storm Dry’ (no I am not sponsored by them, I’m just a building inspector). This is a breathable membrane which is applied to the exterior of the masonry which is totally water proof but allows the masonry to breathe and release moisture from within the wall itself. It is also guaranteed for 25 years and drys clear and colourless. If you have cavity walls and you have areas of damp, remove a brick on the outer leaf where the damp area is and check that the cavity is not blocked. If it is then clean it out and maybe replace the brick with an ‘air brick’. If the cavity is clear then look under the floor to the internal leaf and make sure the dpc is not breached by previous ‘builder’ activity. Any joist ends should be checked as well where there is a breach to check there is not rot to the joist end. The ultimate dpc failure test is to do a ‘Speedy test’ although this test equipment is usually only used by remedial treatment companies.
It all started with a tv dicumentary in the 1990,s which said it was a ventillation problem .They placed a stack of bricks in a tray of water six inches high and the moisture etc never went up the stack of bricks.
I had a damp issue in my last house, solid brick Edwardian end of terrace. The council had relaid pavement ok the side of the house prior to us buying. I didn't realise that this would cause an issue when I bought the house, but the level of the pavement, outside was higher than the floor in the house. So yeh, damp in the walls. I spent blinking hours on the internet researching the issue and came to the conclusion that there wasn't much that could be done. Previous owners put an injected DPC in the walls, but this just trapped the moisture between the floor and the injected DPC, so any plastering between these would just blow eventually. The council were never in a million years going to install a French drain between the pavement and the house to stop prevent the issue. I sold the house and the new occupants tanked the wall, I would be interested to see what that did, I would imagine that it would damage the bricks eventually as there would be literally nowhere for the moisture to go.
Seen council contractors do this. Who cares when all you are interested in is how much per square metre you get for laying flags. Don't let the council fob you off. They caused it..
Very well balanced and reasoned. I believe in rising damp! However, I'm less sure about certain parts of the damp industry. First comes the general surveyor, who sticks his moisture meter into various surfaces and opines that there might be damp and recommends a specialist. But there aren't really specialists, or many of them anyway. There are only firms that cure damp, using a variety of methods. But was it damp in the first place, or condensation? Well, these firms aren't going to say it's the latter. This was my experience when I bought my house seven years ago. The firm I engaged diagnosed damp more or less all through the ground floor. The remedy, to hack off all the plaster (filling up a whole skip in the process), injecting some kind of gunk and then re-plastering with plasterboard and skimming. So the damp appears to be cured but I have the feeling the whole thing was over the top. (And my pocket felt it at the time, to the tune of c £2500). The dry rod method which you recommend looks a lot less intrusive and more economical in expense and time. Were you on UA-cam seven years ago?
No, it is a misleading term. Old houses were designed to get wet, hold moisture and dry out. Moisture moved through the building in something (as he explained) called capillary action. Eveyr piece of timber has it. ,Every solid piece of masonry has it. We all agree capillary action is here to stay. We he dont get is that the "rising damp" he is getting all confused. HE should think "trapped moisture". "Trapped Moisture". That is moisture that is trapped because it cannot escape. This trapping is caused but he Damp industrys remedies. I see it EVERY day in my work. Even he says cement renders trap moisture. I wish he thought things through.
It might be more to do with the over keenness to just shout RISING DAMP and then rinse loads of money from the home owner. When more often the fabric of the building itself has been corrupted such as blocked airbricks below floorboards or even overflowing gutters, I just dealt with damp in the middle of a 1st floor wall. We found the condensing boiler outflow pipe hidden behind a soil stack and the plumber had returned the pipe to the wall and moss had built up creating a bridge for water to penetrate.
A well known local damp proof company recently hacked off and rendered to 1.8 metres when thirty years ago it was 900mm, fifteen years ago Is was 1200mm. This tells me that the capillary action is simply climbing further with each increase. Pointless. Somebody needs to tell them that trees can draw water to over 100 feet just through capillary action so what they are doing is just fighting a losing battle.
And the answer is 'Yes!' This is why you don't see sodden saturated bricks on canal bridges!!! The only Rising Damp I have ever seen is the comedy starring the late, great Leonard Rossiter :).
@@dannymurphy1779 most buildings with damp issues don't even have a DPC and that's the problem. The implementation of modern building methods on old buildings is creating damp.
the best way to prove damp rises is to use a length of twine draped over something with the bottom dipped into a glass of water leave for two to three hours and viola the full length of twine is soaked
We have a copper coil. When we bought our house the surveyor said we had damp, with their stick indicator, the company who put in the coil and guaranteed it said nope. 30years later we have no problems with damp
It can be but it's more simple than that. The simple answer is what Rodger said, we live on the earth that is wet and cold, the air temperature is higher than the groung temperature so the moisture rises. Ventilate and most of the problem is solved. I know it's expensive to heat and ventilate at the same time, so send your problem to the government because they are the ones who are taxing you and ripping you off with fuel prices. I'm in Bulgaria and it costs me £200 to heat my house for the winter and thats 24/7 with wood burners. A normal winter is 5 months long with temp's down to - 20. Rodger mentioned lime mortar and my house is held together with lime mortar and no mould anywhere.
A common cause of rising damp is when someone raises the earth or pavement outside the building so it is above the damp course. I've known people who have had treatment for damp in their bricks when they just needed to lower the earth level outside to be below the damp course. A damp proof layer made of slate with waterproof cement will never fail with age.
I am a bricklayer by trade so I tend to notice these things. You are 100% correct, I have seen it so often it makes me want to scream. Ground level should be at least 150mm below the damp course.
@@TomTomTomTom538 It enters the wall and rises, ergo it becomes rising damp. Most rising damp is because of some fault that occurs that has nothing to do with the buildings original construction.
For many reasons Lime mortar still has its virtues and must always be considered when working on lime buildings today, Many a project has gone wrong when repairing or repointing period lime built properties with Portland cement,the two are not comparable. It went out of mainstream use when Portland arrived and proved more effective for all year use and less know how needed. Also and little know another contributory factor was the first WW, Portland was just beginning to overtake lime in it’s use and the tradesmen who knew this art went to war and didn’t return accelerating the demise of lime. It’s only recently we have recognised its value and place and thanks to a small dogged band of devotees have brought this wonderful stuff back into use. Roger! you mention about lime mixing hazards but Portland cement is almost as bad when mixing on a breezy day.
@@SkillBuilder depends where you live Roger, in modern suburbia there’s little point in merchants bothering to stock it. Here in East Anglia there’s a very large period housing stock and merchants sell it alongside Portland. Lime buildings have been around for thousands of years, The Romans used it and in many cases these buildings still in tact, which won’t be the case for Portland build. Of course lime doesn’t sit well with the modern desire to speed everything up and you can’t or mustn’t use it in winter conditions which severely restrict its use to more specialised construction and repair. I’ve a two hundred year old lime solid wall house and putting an extension up in lime. I love everything about lime from breathability, movement and even acoustics with internal lime plastering.
They should fix the source of the problem, mustn't be adequate ventilation/no damp proof course/something breaching the damp proof course. Hope you get it fixed.
Hi Peter There is an open invitation to Peter Ward and even Jeff Howell to debate this subject on Skill Builder but, so far, they have not taken us up on it.
I think you’ve missed the point. Moisture will only wick up a porous material. If you put an engineering brick in a bucket of water the exposed bit will stay dry as opposed to a thermalite block which the water will travel up. Same story with mortar, Portland cement is pretty much waterproof. As you say, almost any structure built in the last 200 years has a DPC whether slate or plastic. I’ve yet to come across a building that was actually suffering from riding damp. It’s always been raised ground levels outside, poor drainage/gutters, leaking pipes etc, drying washing inside, modern showers, leaking roofs. Most of it can be solved by simple stuff like lowering ground levels. Dealing with rain water ventilation etc. So in a way I’d agree rising damp is a myth. The products like dry rods, injection creams, galvanic system etc are 100% snake oil.
I bought a terraced house in 1985 that was 100 years old. Good gutters, roof, drainage. All walls in the downstairs rooms were damp up to about a metre except for the extension that had a dpc. Hacked all the plaster off, damp course injected, replastered. Damp was back within a year. All houses in the row were the same, but not really a wet area and were at the top of a hill. I reckon it was the mortar mix that had been used, but rising damp does exist.
@@OggyGTA I didn’t say it didn’t exist, I said I’d never actually seen it. You didn’t he standard builder fix that just masks the problem for a few years, that’s why our damp came back.
Thanks for name dropping my local town Roger- Back in my school days we had a trip to the NORI brick factory and even got to bring a sample home. Good paper weight and cemented the brand in my mind to this day (pun intended).
Rising damp is very common in Ghana and people are just tiling thinking it's solving the problem. Eventually it rises above the tiling level to a point beyond repair. The blocks here aren't very good either.
@@danielknight3940 I started on an internal wall that I was actually going to cover anyway just to practice. I was starting from zero experience of repointing but it you've prior experience with cement I think the major differences are in the mixing you need to mix it more carefully than cement and more thoroughly. Get it to a very stiff mix phase first - by stiff I mean dry but not so dry as it's "balling" i.e. you're getting tiny gravel like pebbles. It needs to go just past that so it has enough moisture that it will clump together. Let it sit for 30 mins at this stage before adding water to get it to your desired consistency (normally still pretty stiff for repointing). I used NHL 3.5 so it's not quite as involved as doing a lime putty I believe. Wet the wall down about an hour before you start, lime needs moisture and CO2 to crystalize into its solid form. If the bricks are too dry they will pull the moisture out the mortar and it'll be chalky rather than solid. I tend to use a garden sprayer and start an hour before wetting down the areas I'll be working on and I keep adding a bit of spray every 30 mins or so to keep it damp. Good luck!
I have a problem with falling damp, i have been told this is due to gravity....the moisture can't escape because it is stopped by the damp proof course.
Wimpey International, (No longer in business) had many columns of various bricks with different strengths of mortar Etc. No damp course standing in water for over 30 years and guess what, damp fid not rise through the mortar course or the bricks more than 0.1mm. Conclusion by Wimpey Labs... Rising damp via brickwork does not exist. Water runs horizontally.
Excellent rant. The topic doesn't interest me but I love a good rant, whether it's me doing the ranting, or listening to someone else's. A good rant is one of the best forms of entertainment.
You may have encountered rising damp that has evaporated. If the house has no damp proof course it will carry on doing that, contributing to the moisture in the house which then forms condensation. This is the problem with 'let it breathe' brigade. Of course you can let it evaporate but that is not a cure.
My air vent bricks are 8 inches lower than my patio n when It rains hard they fill up with water over the air bricks lol would this course damp ?and next to a gutter drain pipe
Simple experiment stand a brick end on in a tray of water and leave it for a week. If you check the brick you will see it will have darkened as the water rises up through it. Water will always rise through capillary action. FACT. Great video.
What is the point of putting a bit of plastic around a row of brinks to stop the damp, if they then put so much cement on the brinks that the plastic get covered over??
I have a problem with rising damp in my underground garage in my new build town house. Bessa blocks were used on interior wall, and I wonder if they can be drilled like bricks shown in Roger’s demonstration. It seems odd that damp proofing was not used in construction, as it appears a problem to be expected with 10 feet of soil abutting the garage wall. Any responses would be welcome.
An interesting over-view of rising damp and some good points made. I suspect the general consensus is that RD is not a myth but its is often mis-diagnosed. In fact the Building Research Establishment have produced a number or papers that deal with this subject, therefore they clearly take the view that RD is indeed an actual phenomena. It is interesting to note however that they report that RD is relatively uncommon. In particular BRE Digest 245 provides guidance on the diagnosis and treatment of RD. It appears that if soil moisture is able to evaporate sideways at low level it will not rise very far whereas there is almost no limit to its rise in cases where solid walls are given impervious or highly vapour resistant coatings. I also understand that a normal 4 person household generate between 7 and 14 litres of water per day in the form of water vapour and that high air moisture content can lead to condensation (surface and/or interstitial) to the base of cold external walls and that these symptoms are very similar to those RD, although, as you say, condensation is a cold weather issue. The key point is that the need for and method of damp treatment should only be decided upon follow a thorough investigation and correct diagnosis. BS 6576 & BRED 245 are of particular relevance in this regard.
I used one of those injection cream damp proofing products in my house about 6 years ago. I took the skirting off today in the under stairs cupboard and the wall is as wet as ever, a complete waste of time and money.
@@SkillBuilder. Definitely rising damp. We have a high water table where I live, there has been a lot of subsidence in my street, some houses have dropped by a few inches over the years. The houses are 112 years old and are workers cottages built on marshland. One neighbour wanted to extend so he ended up demolishing the whole house except the front wall as the back had dropped by nearly 4 inches and all floor joists were rotted at the ends, I think it was caused by the render trapping water in the walls. They removed render from the front wall but it was so hard the bricks were destroyed by the removal and had to be rendered again.
@@SkillBuilder I tell ya, these energy saving bulbs jus ain't that bright enough to illuminate that part of moon. No wonder why I missed it 🤔😅poor spitfire didn't stand a chance 😕
Rising Damp is not a myth. I've seen a few episodes and thought Leonard Rossiter was absolutely fantastic.
😄
Very funny, I wished I had thought of that. :-))))
@Anglo Saxon Motherland. Detectorists.
Haha!
@@manfromdelmonty303 Always brighten up a dull day with a laugh
Quite a balanced view Roger. Most older housing stock remaining in London was built without damp-proof courses or cavity walls and in the main stays remarkably dry. But ground levels have risen after various owners lay yet another layer of paving over old, until outside paving is level with inside floors. Walls are rendered and painted instead of being left to breathe. Chimneys blocked up and plastic windows installed. Overoccupation of ever decreasing sized properties then pours water vapour into what has effectively become a plastic bag. Cooking on gas releases even more water vapour. Result is condensation, as you described so well, on the colder surfaces. The rising damp myth a book by Jeff Howell the building science lecturer does put a big hole in the damp proofing industry but the RICS are equally to blame for allowing their surveyors to hide behind their damp meters most of whom have no idea of their serious limitations.
It isn't that it doesn't exist it is more that it is often misdiagnosed
I think the problem was with the rising damp industry is they were a lot of scam artists that attributed all damp as rising damp and charged thousands to solve a problem that wasn't there. It was condensation or penetrating damp, especially in old building where the outside ground level had built up above the hard brick course or above vents.
I agree with the fact that people misdiagnosed to make a quick buck but to go from there to saying that rising damp is a myth is nonsense.
@@SkillBuilder There are people that go too far on both sides, those that believe moisture cannot go up a wall under any circumstances and those that believe it can wick up a brick or even a stone. And both sides are as stuck in their ways as flat earth folk are. All I know is I took all the cement pointing off my wet 3ft thick sandstone wall (built 1685) and water came out of it for a week. Lime pointed it and it's bone dry inside and out now, BUT ... I reckon it needs the log burner in the hearth to keep it that way.
@@phoenixdundee Exactly what he says, water is no longer trapped and evaporates into your house but it still goes up the wall. Question is what happens on the inside? I suppose more ventilation and higher heating costs?
@@SkillBuilder In my view Rising damp its not a myth its a Fact ,
just ask any flat owner who has a basement flat for a while he can comfirm and tell storys :)
not pleasent ones , been working with surveyors and flat owners for last 12 years around London and on basement flat happens a lot .
Im not a builder but i was wroking close with contractors and surveyors from start until the project end can say its not a myth .
All the best Roger
@@porter761 I agree its real, but in a basment it would be penetrating damp.
I have a customer with a small mould issue, no trickle vents, clothes dried on radiators , north facing gable with cracked render, etc etc. Gave the customer some advice, but he opted for getting a plasterer in who hacked off the first metre and then reinstated it, a practice synonymous with rising damp. Only issue is it’s a second floor flat!
What's the gable built with? Stone or brick/block? And is it cement render? If its stone with cement render, then that's your problem right there.
I've seen damp getting through about 40cm of wall laterally when the outside render was cracked, and these were very small/hairline cracks. The wind also helps drive it in I think.
Dehumidifier required.
@@stonemasonlew9349 it’s a solid brick built gable with a cement render. The render is cracked and north facing. My point was that the damp would have had to jump from the ground floor onto the second floor therefore making the plaster/render hack off a waste of time!
@@thesunreport agreed, the 3 story Victorian building is on the coast, so driving rain is definitely an issue. I had suggested repairing the cracks in the render and then coating with storm guard or a similar product, more adequate ventilation, the cessation of clothes being dried on rads and so on and so on. The decision to hack off and re render/ plaster is a waste of time as I’ve never known rising damp to jump from a ground floor to a second floor!
The source of damp is where the confusion comes in. A lot of time it's poor ventilation or penetration.
I don't think anyone really believes that rising damp is a myth do they? It's just that 90% of damp cases are not rising damp. I've even seen cases where there is a perfectly good original slate damp proof course and some damp roof cowboy has drilled holes all above it to 'treat'. And of course it didn't fix the issue because it was a high ground level and breathability issue
Exactly, easy things first. Use your eyes! :)
Well said Tom , Bisby thinks we’re all idiots and by shouting thinks his opinion is always right.
As a Building Surveyor, I don't think I've ever met any qualified surveyors who would argue that rising damp doesn't exist at all, just lots who (I would say rightly) believe that the cause of the damp is usually more likely to be something else.... i.e penetrating damp from the exterior, raised exterior ground levels, poor ventilation of underfloor voids, poor choice of plaster/render material, condensation etc etc.
The chemical DPC industry is still a bit of a racket, in my view. I have never specified one, though I would never rule it out completely, i'd just want to try lots of other things first!
Some of the confusion comes, I believe from some research which was done some years ago at London South Bank University, where they were not able to recreate rising damp in lab conditions. Clearly, lab conditions are not necessarily indicative of the real world, and I took the outcome of the research to be that water moving upwards via capillary action is simply a lot less common than some people think.
I wish people would replace the words "RIsing Damp" with "TRAPPED MOISTURE". They their brains would be focussed a little better. Capillary action is real. Solid walled buildings are real. Moisture travels from the ground to escape outwards UNLESS its trapped by cements /plasters etc etc THis guy has done himself no favoure. Just comes across as a rather thick, ranting builder! The sort that we earn good money from undoing all their non-working solutions.
If rising damp does not exist, which do modern regulations specify a pvc membrane for cavity wall brickwork.
@ Numero uno: Maybe because it is necessary to have a DPC ...It is a modern way of building using cement and modern brick, for speed and cost etc (but don’t forget all the houses (cavity) that have their internal and external walls ‘connected’ by poor workmanship (cement droppings bridging etc) and what do you get apart from huge repair bills ? Damp walls or wet walls STILL ! (Even with a DPC !) Some would say rising damp ! Then presumably charge a fortune to ‘waterproof’ inside or outside and or damp injections etc etc further reducing evaporation...You have to be careful ..Cement is a huge polluter of CO2..global warming ! many old buildings were fine and dry until modern materials (cement) were used to repair..leading to “so called Rising Damp ‘...Majority of housing stock does not have cavity walls traditionally, so you need to head back to ventilation humidity breathability for those...
Cavity walls a fine modern initiative, (except for the pollution/warming etc) and still suffer condensation ! SO...maybe extra jumper in winter..Can’t have yr cake and eat it !? 3:29
There is no confusion and you don’t need a lab to recreate rising damp. Simply put a brick in 5mm of water and leave it there. You will physically see it rising!!!!
Flat earthers!
What an excellent comment from someone who obviously knows what he’s talking about, quite noticeable that Mr Skillbuilder hasn’t commented !
British terminology : rising damp
Rest of world and science : capillary action (or wicking)
So true mate. Only trapped moisture caused by natures very own capillary action. Even trees have it .....ooops - HE said that!
I've renovated a few houses now and had to remove bricks behind skirting to access the cavity to scrape out cement snots. Worse on houses built 100 years ago with lime as some of the lime crumbles down over time. I then attatach a length of waste pipe to a Henry vacume cleaner and suck it all out.
Ah Venice, a place where the rising damp is so bad, they use gondolas for transport on it.
Buildings need to breath because of the condensation caused by people living in it. Trapped condensation - trapped by modern "damp proofing" methods. It's almost always never actual rising damp, that's the reason given for expensive remediation work.
Yes!
Now sure whare you live but are you saying people generate more water than the English weather?
In the distance I can hear Peter Ward exploding.
I'm a rocket scientist, and I've been to space and I can tell you rising damp is a myth. It's actually aliens pissing against your house at night... and the earth it flat 🤣🤣🤣🤣🤣🤣🤣🤣
20 years ago, we were on holiday in Florida at a fast food outlet. It was October, the outside temperature was around 85 deg F (30 deg C), the restaurant was air conditioned. What I remember seeing was massive condensation at the non double glazed windows, caused by the temperature inside the restaurant (around 66 to 68 deg F, 19 to 20 deg C) meeting the hotter air outside.
Bought my house (1930’s three bed terrace) about 9 years ago.
Was told by surveyor that it had rising damp (rotten floors, damp walls ect)
On closer inspection the exterior ground levels had risen above the damp proof course
Took ground levels back down fixed all damage caused problem solved 👍
So the surveryone was rihgt to say it had rising damp but did not show the cause. This is often the problemm they simply say to get it diagnosed which often means another surveryor/salesman. That is the disconnect.
Britain’s expert and guru on damp
In buildings is Pete at Heritage House Building and Restoration. He’s an RICS conservation surveyor. I recommend reading their website and watching the videos. It’s eye-opening and very informative. He should be given an award for his relentless exposure of unnecessary remedial works and the real causes of damp. Actually, he doesn’t really believe in rising damp!
And incidentally, why show Venice as proof of rising damp? It’s built on water! Most British Homes at worst, would sit on slightly damp soil for part of the year.
Agree with what he says ,roger is having a rant
Just to be clear. Pete is not an RICS accredited conservation surveyor and I hope he is not claiming that. He doesn't hold any notable UK professional construction qualifications and his views are not particularly expert or revealing. Misdiagnosis and application of inappropriate remedies by unqualified people in the damp and conservation sector is by far the most common problem leading to manifest damp penetration. Venice is a classic example of the physics of how water can move through building materials including rising from below and has been a factor known of for centuries.
Knowledge is king, and Roger have more than his fair share of it bless him . The first house I ever bought I did a silicone injection system , which I did my self , it tuck me about 3 days to complete . At the time a lot of companies would have done it in half a day , because they didn’t allow enough time for the silicone to penetrate into the bricks . So it was a totally waste of time , knowing this a pumped as much as I could in till I saw it coming back out of the bricks and mortar . Well that was some 40 years ago now so it would be interesting to see if my efforts payed off in the long run . Thanks again Roger for your tieless work in bringing this to everyone’s attention, because silly statements like your describing could cause a lot of problems for people. Best wishes and kind regards as always 😀👍👍👍
Pizza+beer+Roger rant=ultimate evening
Great video Roger, I'm a Chartered Structural Engineer and you were able to sum up the issues at hand here in a very concise way.
Really what most of the people saying rising damp doesn't exist mean that it isn't the main cause. Most people know that when you get called out to a damp issue if it isn't a basement it's going to be landscapers that just completely ignore the dpc and air bricks (yes the brickies point of veiw 😂). And if it isn't that there's leaking guttering or drain. But rising damp actually being the main issue isn't it most of the time, yes the injection damp proofing is probably going to be the most cost effective way after you've spent a few k on getting your new paving.
What a reasoned argument you give Roger, scientific, balanced & not biased or ranting in any way. BTW: a) how much damp do the Dutch suffer? b) Who says damp cannot rise? it can but not in masonry, it is when the cement is bridged by porus materials such as plaster or a render which creates a capilliary gap..
Interesting rant on Rising Damp.
You are right, on many levels, including that condensation is commonly misdiagnosed as rising damp.
And that a DPC is useful for stopping water rising-up a porous brick.
What many people don’t understand is:
1. Rising Damp is defined as the rise of moisture from groundwater.
2. Groundwater being water under the water table.
3. Rainwater in contact with a wall may result in rising damp like symptoms but unlike groundwater, rainwater in soil, can and should be removed through improved drainage.
4. The rise from rainwater in soil is considerably smaller than from rising damp as the soil is unsaturated and therefore water will mainly be drawn down, not up.
5. Like rainwater and groundwater, water from any source can be absorbed up a porous brick, including condensation of a solid floor.
6. Condensation within a wall causes heat loss increasing the risk of condensation. Gravity drawn moisture down and the base of a wall is normally the coldest part of a wall. So condensation is most commonly found at the base of a wall. It expands upwards as condensation increases, for that reason condensation in a wall often appears to rise, leading to condensation commonly being misdiagnosed as rising damp.
7. Chemicals and damp proofers slurry may hide condensation or water from defective gutters etc. for a while, but unless the root cause is dealt with, the moisture will eventually show through.
Interestingly no wall suffering from rising damp has been preserved so that it can be studied and learned from.
There was an attempt a few years ago, but the wall dried out when it was covered.
I agree with the points you make but I would suggest that the University of Bolgna has many examples of rising damp and carries out trials in many historic buildings
Been to a few jobs (usually let properties) where they've claimed it was damp all of the time. Turned out the first metre of roof felt was knackered and rain was trickling down the cavity.
Blocked gutters are another major cause of damp in homes
Nah. People always say that
As you rightly say, in older buildings, clear out the cavities where snotts over the years have fallen and built up over the DPC level, especially where lime mortar was used in construction, and make sure that exterior ground levels are 6" below DPC, old buildings need to breathe!
Peter Ward will have a fit
@@ian_s7481 ..lol, yes. I love Peters videos although he hasn't done much lately.
Ah you're brilliant. Love your work. I've seen a mock danger sign "translated" from Japanese: "Danger: do not dumb here. Dumb free area." You need one for your shed or whatever.
I was dying for the toilet, but I saw this video and had to watch it. I'm now experiencing my own rising damp issue.
Falling damp, you mean.
Excelland and justified rant Roger ! Damp in buildings is a complex issue and like you say many people are not aware of why it is happening. Most people don't have a clue about how much water is released into the air inside the building each day. Moisture given off by the people living in the building, washing drying, showers, baths etc. Gallons of water floating about in the air which In the hemetically sealed buildings we have to day has got to go somewhere. There's little to no ventilation to the outside to carry it out. It will find cold spots in the building and condense and then black mold will eventually appear and the panic sets in then ! And yes, rising damp does occur - but to different amounts in different materials. Semi-engineering bricks an fresh mortar are usually pretty good at preventing rising damp as are dense blocks. But once the building gets older the mortar starts to break down and that is when it loses its water resistance and damp will start to travel up the mortar joints. The amount of times I have seen perfectly good blue bricks in old buildings that have been drilled into and chemical injection supposedly injectedinto them !! Totally ignoring the cause of the problem which is the mortar in the joints that's failed..
You sorted my head out of fear 😊. I am moving to my last home in my senior years with little funds. You are teaching really helpful information. I will have a go at fixing my damp bungalow. Thank you for helping me out.
Love the way you present your advise. Great channel.🙏
Cracking rant! We had rising damp in our old utility room- the walls were literally damp to touch when we moved in.
DPC was being bridged by some badly laid concrete. Cut out the edges, and left a gap between the slab and the building. Left the plaster as we knew the room was going tk be replaced.
Dried out within weeks and stayed bone dry for 4 years until I knocked it down.
On the subject of DPCs you have to understand they date back to a time when buildings were put up using hand mixed porous lime mortar and a huge variety of vernacular materials of varying properties and quality. They make little sense in modern buildings built using OPC and hard fired bricks, yet modern builders seem to be obsessed with them. There is a long standing idea that British houses are built in swamps with only a thin strip of plastic between warm dry comfort and crumbling soggy walls. If the ground is wet then people need to find out why and not just squirt some chemicals into the walls. With damp you have to fix the cause and not the symptom.
I'm only 1.5 minutes into your vid Rodger and already I know that you are correct. I'm from England and now live in the balkans, Bulgaria. It's a range of mountains that weave through europe like a snake.
I have a two storey house, downstairs is natural stone and upstairs is homemade or village made brick.
I am surrounded by mountains and I can watch the clouds being made and rising from the earth from my window, when this happens the temperature drops in my house and I can feel the damp coming up from the earth.
I live upstairs only, downstairs is great for storing food and making wine, it has a temperature that is more stable. In the summer it can reach 42c upstairs and remain 25 downstairs.
I would say that rising damp is natural, it's the mold that's unnatural because of the lack of ventilation.
always keep your home ventilated and most of the problems will disappear.
Thanks Rodger.
I agree completely, problem is when these companies turn up and sell you a damp proof system after using a silly meter on your walls. These damp proof systems cost thousands and in reality you probably just need to redecorate or open a window in the majority of cases, my house being one of them.
We purchased a house that our surveyor said needed a full damp proof system installed, cost the previous owner 14k before we could buy it. It now has a stupid layer of concrete on the lower half of the walls that does absolutely nothing other than potentially caus damp issues itself.
After spending 3 years renovating the house and seeing the condition of the brickwork, it has no signs of damp anywhere, bricks are bone dry.
In this country also, mortgage companies listen to surveyors whenever damp is mentioned and demand a damp proof system be installed before it can be sold. The industry is all wrong and needs sorting out, sooner rather than later.
@ matte : I agree whole heartedly (as I fell foul of that system many years back-and it too failed after a few short years..) Old stone wall etc BUT concreted and DPC floating floor done many moons ago unfortunately 3:38 .. So soil damp rising still rising through walls causing salt damage etc.. Nobody living there now therefore cold ish and needs time to dry out and breathe plus normal heating ..Hopefully it will get better...But those damn Floors ..too expensive to renew with limecrete breathing type floor and physically beyond me now..
I’d like to see a video about the most common building control fails, or maybe some of the more obscure regs that people miss. I’m surprised building inspectors aren’t more stringent with keeping the cavity clear
Your last sentence, I couldn't agree more with. I imagine it's difficult to police, or time issues on getting it inspected (does somebody have to inspect it before the roof/joists start going up?).
@@lloyd4011 they don’t inspect before joists. They’ll usually pay a ten minute visit once the structure is built before insulation but as the cavity is usually full of insulation, wouldn’t be able to see the the damp course to check it’s not bridged.
As a building surveyor for over 40 years I did 15 inspections a day for 4 days a week 1 day writing reports. Of those average 15 inspections three quarters would be to inspect rising damp lets say 10 inspections for rising damp of those inspections only 1% would be water penetration. The test used is one that is accepted by the courts or arbiter A discreet hole is bored in the affending section of wall and the colour of the dust is registered ie if the dust becomes lighter it is condensation. If the dost becomes darker it is water penetration. If it went darker it is water penetration. The then would be weighed and then subjected to a gas pressure vacuum and the dust re weighed establishing a penetration ratio the water is tested 1st for chlorine if present it is domestic water, then for glycerene which shows it is from a leaking central heating system then it is tested for traces of effluent which would indicate a broken drain. We are advised not to use the term rising damp as this implies water traveling vertically. Water is very heavy and for it to go vertical it must be pumped. There is an argument it can be drawn by capillary attraction so is it through the brick is the brick a soft porus brick or is it travelling through the joints? At Building college built dwarf walls using different bricks bult in galvanised trays never observed water travelling upwards except when more water was put in the tray. Seen plenty of water penetration usually poor cavity trays, parapet walls. Most of my work was by the Thames some of the structures 2, 3 maybe 4 hundred years old Sam Pepys office at the old Deptford Navel yard comes to mind, no damp course, snuff dry. Of Course the well built survives the dross goes into history. I think water penetration is a better word Rising Damp is a television programme. Good rant though.
@@jeffhenderson9595 If the inspection is condensation and in most cases it is observed instantly it is down to life style they would receive a very comprehensive booklet or I would arrange one in what ever language they required. As it is social housing the visits would be selected close together. We tried to work an 8 hour day which gives 1/2 an hour per visit though allegedly we were on flexi time. We were issued with mobile phones so we could inform the resident how we were doing. The call center only confirmed am or pm appointments. As Local Authority employees over a certain grade we were expected to attend evening meetings some council meetings. some tenants asociation meetings sometime because the resident worked shifts an evening visit was arranged. The call center would arrange the appointments and log the description as stated by the resident which would be rising damp
That was a fine rant tonight Roger 😃.
What about the surveyors for mortgage companies that used to say virtually every house need a damp proof course installing, I’m sure often it was condensation or damp caused by other things such as faulty fall pipes etc. Not bought or sold a house for many years but remember all those surveys well from the 80s and 90s. It’s just the rich tapestry of life.
If there's no such thing as rising damp, how about 'falling damp?' That's usually caused by leaking roofs or faulty plumbing. Using a meter, rising damp can be detected in walls quite easily. Love the botany lesson, Roger. David Attenborough, watch out. Very informative post as an analytical chemist myself, now retired, the use of silicone fluid to help damproofing courses more effective still interests me. My house is a 90 year old 3 bed semi, built with Accrington brick, one live chimney and central heating. There are now issues with rising damp 40 years after the DPC was done, time to call in the experts for a survey.
Put the tip of a towel in some water and watch what happens! Simple. However I assume most people get confused as a lot of damp problems in houses is either poor guttering and drainage or sweating inside
No it's a comedy show Lenard Rositer Epic show I still watch to this day!!
Miss Jones
Fantastic rant Roger, hardly stopped for a breath!
Very informative and I reckon you could bust any myth😄
😂😂😂
Good rant
Saw you the other day at selco
Not gonna lie i was star struck
Had to do a double take
Couldnt get my words out
😂
Which selco
Hi Lee
Fabulous thumbnail picture for this video.
The last time I saw that expression deployed to such great effect was by Kenneth Williams. The subtitle should be “Ooh, I have never been so…”
Also of damp issues are also to do with showers in every home, they create a lot of vapor and it settles on cold walls so if you have a cold home it stays
I was under the impression that damp would only rise about 30 inches ? That's what we were told at college. I saw a
documentary several years ago. It was made by a chap who goes around doing inspections on houses for house buyers.
He said that in all of the inspections of damp he had done over many years, they were rarely caused by a faulty damp
course. there are many ways as to how moisture can penetrate a building. Ground level, faulty RWP's etc.
The idea that rising damp won't go above one metre is false. There are lots of examples of it going above that but if it is allowed to evaporate then is will do so in the first metre.
@@SkillBuilder I had rising damp in a house I rented. There was salt coming through and most of it was roughly a metre and some was way higher.
Excellent rant Roger and totally correct! I did work for a remedial treatment company in the early 90’s. In hindsight I only found one case of ‘real rising damp’ where the damp had risen to approx 900mm which was in an old empty house, quite fascinating to behold if I’m honest, it was a textbook case.
The ‘failure of the damp proof course’ is in the main a myth in my experience. The main cause of damp in properties is down to many issues; condensation, blocked cavities, hygroscopic salts, penetrating damp where walls are solid, and one of the worst in my experience ‘sulphur salts’ caused by penetrating damp down a chimney where no cowls have been fitted and the chimney is no longer in use as an open fire place. In my experience chimney breasts do not have a dpc and once decommissioned as an open fire tend to suffer with rising damp as well as penetrating damp where rain can get down the flue and they are not vented. If used as a flue for a gas fire, this is further exacerbated as gas is a ‘damp heat’. The end result is yellowing damp patches on and around the fire place.
If you have solid walls and suffer with penetrating damp then I would recommend ‘Storm Dry’ (no I am not sponsored by them, I’m just a building inspector). This is a breathable membrane which is applied to the exterior of the masonry which is totally water proof but allows the masonry to breathe and release moisture from within the wall itself. It is also guaranteed for 25 years and drys clear and colourless.
If you have cavity walls and you have areas of damp, remove a brick on the outer leaf where the damp area is and check that the cavity is not blocked. If it is then clean it out and maybe replace the brick with an ‘air brick’. If the cavity is clear then look under the floor to the internal leaf and make sure the dpc is not breached by previous ‘builder’ activity. Any joist ends should be checked as well where there is a breach to check there is not rot to the joist end.
The ultimate dpc failure test is to do a ‘Speedy test’ although this test equipment is usually only used by remedial treatment companies.
Oh you’re one of them ……..put our liquid in don’t find out the real reason for damp being caused
It all started with a tv dicumentary in the 1990,s which said it was a ventillation problem .They placed a stack of bricks in a tray of water six inches high and the moisture etc never went up the stack of bricks.
Yes it was a completely flawed experiment. It proved nothing.
@@SkillBuilder Well leonard Rossiter had it.haha stay safe and well like yr vids
Thanks Roger, your rant has brightened my Sunday morning!
I own an Edwardian house with rising damp... where idiots filled a conduit channel with bonding you could see water stains tracking up the wall. 😡
Our house is 1860, solid walls, slate damp course. No damp.
The slate damp proof course is doing its job. No surprise there
I had a damp issue in my last house, solid brick Edwardian end of terrace. The council had relaid pavement ok the side of the house prior to us buying. I didn't realise that this would cause an issue when I bought the house, but the level of the pavement, outside was higher than the floor in the house. So yeh, damp in the walls. I spent blinking hours on the internet researching the issue and came to the conclusion that there wasn't much that could be done. Previous owners put an injected DPC in the walls, but this just trapped the moisture between the floor and the injected DPC, so any plastering between these would just blow eventually. The council were never in a million years going to install a French drain between the pavement and the house to stop prevent the issue. I sold the house and the new occupants tanked the wall, I would be interested to see what that did, I would imagine that it would damage the bricks eventually as there would be literally nowhere for the moisture to go.
I have exactly the same situation. You didn't help yourself having that surname... ;-)
Seen council contractors do this. Who cares when all you are interested in is how much per square metre you get for laying flags. Don't let the council fob you off. They caused it..
I’ve always put I’d down to capillary reaction. Similar issue when wet rooms are formed with overlapping joint rather and sealed joints.
Very well balanced and reasoned. I believe in rising damp! However, I'm less sure about certain parts of the damp industry.
First comes the general surveyor, who sticks his moisture meter into various surfaces and opines that there might be damp and recommends a specialist. But there aren't really specialists, or many of them anyway. There are only firms that cure damp, using a variety of methods. But was it damp in the first place, or condensation? Well, these firms aren't going to say it's the latter.
This was my experience when I bought my house seven years ago. The firm I engaged diagnosed damp more or less all through the ground floor. The remedy, to hack off all the plaster (filling up a whole skip in the process), injecting some kind of gunk and then re-plastering with plasterboard and skimming. So the damp appears to be cured but I have the feeling the whole thing was over the top. (And my pocket felt it at the time, to the tune of c £2500).
The dry rod method which you recommend looks a lot less intrusive and more economical in expense and time. Were you on UA-cam seven years ago?
No, it is a misleading term. Old houses were designed to get wet, hold moisture and dry out. Moisture moved through the building in something (as he explained) called capillary action. Eveyr piece of timber has it. ,Every solid piece of masonry has it. We all agree capillary action is here to stay. We he dont get is that the "rising damp" he is getting all confused. HE should think "trapped moisture". "Trapped Moisture". That is moisture that is trapped because it cannot escape. This trapping is caused but he Damp industrys remedies. I see it EVERY day in my work. Even he says cement renders trap moisture. I wish he thought things through.
It might be more to do with the over keenness to just shout RISING DAMP and then rinse loads of money from the home owner. When more often the fabric of the building itself has been corrupted such as blocked airbricks below floorboards or even overflowing gutters, I just dealt with damp in the middle of a 1st floor wall. We found the condensing boiler outflow pipe hidden behind a soil stack and the plumber had returned the pipe to the wall and moss had built up creating a bridge for water to penetrate.
A well known local damp proof company recently hacked off and rendered to 1.8 metres when thirty years ago it was 900mm, fifteen years ago Is was 1200mm. This tells me that the capillary action is simply climbing further with each increase. Pointless. Somebody needs to tell them that trees can draw water to over 100 feet just through capillary action so what they are doing is just fighting a losing battle.
good job covering the subject but I'd still never inject an old house
bba certificate so it does work… yes like grenfel cladding , cavity wall insualtion, etc
And the answer is 'Yes!' This is why you don't see sodden saturated bricks on canal bridges!!! The only Rising Damp I have ever seen is the comedy starring the late, great Leonard Rossiter :).
You’re 100% wrong Danny. I work on a lot of Victorian buildings and I see it on a regular basis.
Edit: ok, I watched the rest of the vid.
@@gdfggggg I think you will find it is very rarely the dpc that is at fault though, nearly always the drains or the dpc has been bridged by the patio.
@@dannymurphy1779 most buildings with damp issues don't even have a DPC and that's the problem. The implementation of modern building methods on old buildings is creating damp.
Roger Bisbee is getting all emotional and precious about rising damp . I wish Quantity s Surveyor Lecturers were as passionate as you are
the best way to prove damp rises is to use a length of twine draped over something with the bottom dipped into a glass of water leave for two to three hours and viola the full length of twine is soaked
We indeed got a lot of rising damp in Amsterdam mate
We have a copper coil. When we bought our house the surveyor said we had damp, with their stick indicator, the company who put in the coil and guaranteed it said nope. 30years later we have no problems with damp
"Rising Dampness" is a simple process called capillarity.
I wish it were a little more simple to spell....
@@ricos1497Corect.
It can be but it's more simple than that. The simple answer is what Rodger said, we live on the earth that is wet and cold, the air temperature is higher than the groung temperature so the moisture rises. Ventilate and most of the problem is solved.
I know it's expensive to heat and ventilate at the same time, so send your problem to the government because they are the ones who are taxing you and ripping you off with fuel prices. I'm in Bulgaria and it costs me £200 to heat my house for the winter and thats 24/7 with wood burners. A normal winter is 5 months long with temp's down to - 20.
Rodger mentioned lime mortar and my house is held together with lime mortar and no mould anywhere.
A common cause of rising damp is when someone raises the earth or pavement outside the building so it is above the damp course.
I've known people who have had treatment for damp in their bricks when they just needed to lower the earth level outside to be below the damp course.
A damp proof layer made of slate with waterproof cement will never fail with age.
I am a bricklayer by trade so I tend to notice these things.
You are 100% correct, I have seen it so often it makes me want to scream. Ground level should be at least 150mm below the damp course.
But that's not rising damp, that's just damp caused by high outside levels.
@@TomTomTomTom538 It enters the wall and rises, ergo it becomes rising damp.
Most rising damp is because of some fault that occurs that has nothing to do with the buildings original construction.
@@harveysmith100 well that part I do agree with.
Just love your clear and funny explanation! It all sounds so logic. Keep up the good work!
Dehumidifiers work well removing damp & dry air feels warmer handy in a bathroom
Fix a cupboard to a wall and watch the rising damp ruin it.
Excellent energetic and spirited Roger Rant….I tend to get on a soap box over some issues just like this (maybe worse)😅
Some people say I have a dry sense of humour. I think it is damp.
No just no 🙈
Put some wellies on.
For many reasons Lime mortar still has its virtues and must always be considered when working on lime buildings today, Many a project has gone wrong when repairing or repointing period lime built properties with Portland cement,the two are not comparable. It went out of mainstream use when Portland arrived and proved more effective for all year use and less know how needed. Also and little know another contributory factor was the first WW, Portland was just beginning to overtake lime in it’s use and the tradesmen who knew this art went to war and didn’t return accelerating the demise of lime. It’s only recently we have recognised its value and place and thanks to a small dogged band of devotees have brought this wonderful stuff back into use. Roger! you mention about lime mixing hazards but Portland cement is almost as bad when mixing on a breezy day.
I have worked with lime for years but it is not stocked by merchants and it slows the job down no end.
@@SkillBuilder depends where you live Roger, in modern suburbia there’s little point in merchants bothering to stock it. Here in East Anglia there’s a very large period housing stock and merchants sell it alongside Portland. Lime buildings have been around for thousands of years, The Romans used it and in many cases these buildings still in tact, which won’t be the case for Portland build. Of course lime doesn’t sit well with the modern desire to speed everything up and you can’t or mustn’t use it in winter conditions which severely restrict its use to more specialised construction and repair. I’ve a two hundred year old lime solid wall house and putting an extension up in lime. I love everything about lime from breathability, movement and even acoustics with internal lime plastering.
I can listen to you all day. I have a huge problem with this in my mother's rented house. They just plaster over it and it comes back very quickly
They should fix the source of the problem, mustn't be adequate ventilation/no damp proof course/something breaching the damp proof course. Hope you get it fixed.
Love you Rodger .The only way to settle this is to phone Peter Ward and get him to come around and see and listen to what he has to say agreed !!
Hi Peter
There is an open invitation to Peter Ward and even Jeff Howell to debate this subject on Skill Builder but, so far, they have not taken us up on it.
I think you’ve missed the point.
Moisture will only wick up a porous material. If you put an engineering brick in a bucket of water the exposed bit will stay dry as opposed to a thermalite block which the water will travel up. Same story with mortar, Portland cement is pretty much waterproof.
As you say, almost any structure built in the last 200 years has a DPC whether slate or plastic.
I’ve yet to come across a building that was actually suffering from riding damp. It’s always been raised ground levels outside, poor drainage/gutters, leaking pipes etc, drying washing inside, modern showers, leaking roofs.
Most of it can be solved by simple stuff like lowering ground levels. Dealing with rain water ventilation etc.
So in a way I’d agree rising damp is a myth.
The products like dry rods, injection creams, galvanic system etc are 100% snake oil.
I bought a terraced house in 1985 that was 100 years old. Good gutters, roof, drainage. All walls in the downstairs rooms were damp up to about a metre except for the extension that had a dpc. Hacked all the plaster off, damp course injected, replastered. Damp was back within a year. All houses in the row were the same, but not really a wet area and were at the top of a hill. I reckon it was the mortar mix that had been used, but rising damp does exist.
@@OggyGTA I didn’t say it didn’t exist, I said I’d never actually seen it. You didn’t he standard builder fix that just masks the problem for a few years, that’s why our damp came back.
Thanks for name dropping my local town Roger- Back in my school days we had a trip to the NORI brick factory and even got to bring a sample home. Good paper weight and cemented the brand in my mind to this day (pun intended).
Rising damp is very common in Ghana and people are just tiling thinking it's solving the problem. Eventually it rises above the tiling level to a point beyond repair. The blocks here aren't very good either.
Bingo on not being able to get anyone to do lime, It’s why I’ve ended up stripping cement render and repointing in lime myself!
I'm planning on doing that soon. Any tips
@@danielknight3940 I started on an internal wall that I was actually going to cover anyway just to practice. I was starting from zero experience of repointing but it you've prior experience with cement I think the major differences are in the mixing you need to mix it more carefully than cement and more thoroughly. Get it to a very stiff mix phase first - by stiff I mean dry but not so dry as it's "balling" i.e. you're getting tiny gravel like pebbles. It needs to go just past that so it has enough moisture that it will clump together. Let it sit for 30 mins at this stage before adding water to get it to your desired consistency (normally still pretty stiff for repointing). I used NHL 3.5 so it's not quite as involved as doing a lime putty I believe. Wet the wall down about an hour before you start, lime needs moisture and CO2 to crystalize into its solid form. If the bricks are too dry they will pull the moisture out the mortar and it'll be chalky rather than solid. I tend to use a garden sprayer and start an hour before wetting down the areas I'll be working on and I keep adding a bit of spray every 30 mins or so to keep it damp. Good luck!
@@danielknight3940 get nigel copseys book on it, read it several times, don't use NHL.
I have a problem with falling damp, i have been told this is due to gravity....the moisture can't escape because it is stopped by the damp proof course.
We get emails from a lot of Australians who have the opposite problem
Wimpey International, (No longer in business) had many columns of various bricks with different strengths of mortar Etc. No damp course standing in water for over 30 years and guess what, damp fid not rise through the mortar course or the bricks more than 0.1mm.
Conclusion by Wimpey Labs...
Rising damp via brickwork does not exist. Water runs horizontally.
I have a 220 year old sandstone house that has been pebble dashed and painted after. I have damp 8' up the wall.
Rant so so worth listening too. You have probably solved one of my issues.
Excellent rant. The topic doesn't interest me but I love a good rant, whether it's me doing the ranting, or listening to someone else's. A good rant is one of the best forms of entertainment.
I have yet to encounter rising damp. I've fixed lots of condensation, leaks, failed drains, blocked air vents and misaligned ground levels.
You may have encountered rising damp that has evaporated. If the house has no damp proof course it will carry on doing that, contributing to the moisture in the house which then forms condensation. This is the problem with 'let it breathe' brigade. Of course you can let it evaporate but that is not a cure.
My air vent bricks are 8 inches lower than my patio n when It rains hard they fill up with water over the air bricks lol would this course damp ?and next to a gutter drain pipe
Help would be great to what I could do plz
The end shot of the moon is pretty funny
Love your videos. Great presenter 👍🏼
Mate. I watched Rising Damp in the 80s one of the best sitcoms. I can confirm it existed
Simple experiment stand a brick end on in a tray of water and leave it for a week. If you check the brick you will see it will have darkened as the water rises up through it. Water will always rise through capillary action. FACT. Great video.
What is the point of putting a bit of plastic around a row of brinks to stop the damp, if they then put so much cement on the brinks that the plastic get covered over??
Hi Roger, could you post the link for that Moon video? Sounds interesting!
I have a problem with rising damp in my underground garage in my new build town house. Bessa blocks were used on interior wall, and I wonder if they can be drilled like bricks shown in Roger’s demonstration. It seems odd that damp proofing was not used in construction, as it appears a problem to be expected with 10 feet of soil abutting the garage wall. Any responses would be welcome.
Damp and condensation will become more of an issue in years to come as people insulate downstairs underfloor without increasing sub floor ventilation
I don't know if it's rising damp or not, but I love your rants and they always make me a little moist.
Heat rises? I thought cold air pushes warm air upwards?
Most educated people already know this. Ignore the cooks and keep producing valuable content.
Any advice for damp proofing stone walls.
Don’t ya mad man.
An interesting over-view of rising damp and some good points made. I suspect the general consensus is that RD is not a myth but its is often mis-diagnosed. In fact the Building Research Establishment have produced a number or papers that deal with this subject, therefore they clearly take the view that RD is indeed an actual phenomena. It is interesting to note however that they report that RD is relatively uncommon. In particular BRE Digest 245 provides guidance on the diagnosis and treatment of RD. It appears that if soil moisture is able to evaporate sideways at low level it will not rise very far whereas there is almost no limit to its rise in cases where solid walls are given impervious or highly vapour resistant coatings. I also understand that a normal 4 person household generate between 7 and 14 litres of water per day in the form of water vapour and that high air moisture content can lead to condensation (surface and/or interstitial) to the base of cold external walls and that these symptoms are very similar to those RD, although, as you say, condensation is a cold weather issue. The key point is that the need for and method of damp treatment should only be decided upon follow a thorough investigation and correct diagnosis. BS 6576 & BRED 245 are of particular relevance in this regard.
I used one of those injection cream damp proofing products in my house about 6 years ago. I took the skirting off today in the under stairs cupboard and the wall is as wet as ever, a complete waste of time and money.
Interesting. Where do you think the water is coming from?
@@SkillBuilder. Definitely rising damp. We have a high water table where I live, there has been a lot of subsidence in my street, some houses have dropped by a few inches over the years. The houses are 112 years old and are workers cottages built on marshland. One neighbour wanted to extend so he ended up demolishing the whole house except the front wall as the back had dropped by nearly 4 inches and all floor joists were rotted at the ends, I think it was caused by the render trapping water in the walls. They removed render from the front wall but it was so hard the bricks were destroyed by the removal and had to be rendered again.
Probably caused by using latex paint so the house did not breathe
I live in Cornwall... Nuff said,thanks Rog 👍
Good vid as always Rodger, more rants please👍😉
I still can't seem to find that crashed spitfire on the moon😂
It is on the dark side along with Elvis and John Lennon, Lord Lucan and Hitler.
@@SkillBuilder I tell ya, these energy saving bulbs jus ain't that bright enough to illuminate that part of moon. No wonder why I missed it 🤔😅poor spitfire didn't stand a chance 😕