How to Prevent Frozen Pipes | This Old House
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- Опубліковано 1 жов 2024
- This Old House plumbing and heating contractor Richard Trethewey shows various ways to prevent and thaw frozen pipes. (See below for a shopping list and tools.)
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Time: 1 to 2 hours on average
Skill level: Moderate. Depending on pipe location
Shopping List for How to Prevent Frozen Pipes:
- expanding foam sealant, used to seal holes and cracks in house
- silicone caulk, used to seal holes and cracks in house
- foam-rubber pipe insulation, used to insulate water pipes
Tools for How to Prevent Frozen Pipes:
- electric heat gun or blow dryer, used to thaw frozen pipes
- scissors, used to miter-cut foam pipe insulation
- pipe thawing machine, rental tool used to thaw inaccessible pipes
Steps:
1. Seal air-leaking holes and cracks around home with expanding foam sealant or silicone caulk.
2. Use foam-rubber pipe insulation to protect exposed pipes from cold.
3. Slip foam-rubber insulation over pipe, peel away backing strips, then press the adhesive surfaces together.
4. At pipe corners, miter-cut the ends of the foam-rubber insulation with scissors, then secure the corner joint with foam tape.
5. Before attempting to thaw a frozen pipe, open the faucet.
6. Locate ice blockage, then use heat gun or blow dryer to thaw frozen pipe; don't use propane torch or other open flame.
7. If the frozen section of pipe is inaccessible, use an electric pipe-thawing machine.
8. Find the exposed ends of the pipe, then place one clamp from the machine onto each pipe; the machine will warm the pipe and eventually melt the blockage.
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How to Prevent Frozen Pipes | This Old House
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Who's watching this after the Texas ice storm aftermath??!
This was in my recommended videos a few days after the freeze. Pure luck on my part, but we had our house re-piped with PEX last year and when our pipes thawed, we were back to business. Not so for so many in Houston who have copper and PVC. Our old house was all galvanized pipe, and I had been fighting leaks with pipe clamps for the last few years. I had had enough and decided to get my plumbing overhauled.
I'm here lol!
It’s always cool to get a lesson from al capone
@Renato Laranja 🤣
LOL
Oh I thought it was George Constanza from Seinfeld 😆
😂😂
Hilarious ❤😂.
My solution… I purchased a digital irrigation timer at Lowes that you would normally use on your garden. I have a Orbit brand, Item #604469 Model #24600 about $30 bucks. I attached it to my kitchen sink with a quick disconnect. I set the timer to turn on once per hour around the clock and run for 2 minutes. It was really easy to set and works perfectly. I live in Northern Minnesota in a mobile home. It hasn't failed me yet. My water lines into the house have heat tape but this is my extra insurance….
Nice
Brilliant!
sounds great, wish I could see your set up. unfortunately, the faucets at the sink may not accept a hose connection. Unless a shower head will.
It's Christmas Eve and the Eastern half of the country is in a deep freeze, all the way from Vermont, where I live, to Florida in the South. I shared this video with my Facebook friends in hopes it will help. Thanks for some great tips.
Got My Christmas present today, a busted pipe! Spent a few hours contorted in a cold attic splicing in a T joint and capped the perpendicular outlet because it's all I had. It worked but now I have exposed pipe letting it dry out before I reinsulate. Yeah I had insulation on it but it was just -15c here in NJ
@@js_youtube70 We had a pipe burst Christmas night at 8:30 here in Southern IL. Merry Christmas to us👎🏼
The South does not bury its pipe as deep as the North and they bust sometimes because they get frozen.
Also their is vented crawl spaces in older houses. So its very cold in those.
Cheap foam pipe insulation is garbage. Wrap the pipes in fiberglass tape and then use the foam covers.
I need to move far away from Wisconsin.
oh yeah ??
how about Afghanistan ???
I justed moved to Wisconsin and now I know the stuggles of living here.
Try SD Its better here
We only get a handful of freezes in Houston so what we do is shut off the water at the meter and turn it on in the morning after the freeze.
Probably a good idea to drain a little water from the lines or all of it depending on where the freeze could happen.
Gentlemen, I am very pleased with the information on preventing pipe freeze. Thank you.
Warren Thomas I’ll save EVERYONE here some
Money with this. ridiculous methods!Freezeblock? Really? Sounds expensive. So. The solution is VERY VERY SIMPLE. Hot water recirculating pump. Installs at your water heater and you can even plug them into a smart plug to set a schedule for how often to recirculate warm/hot water because I don’t always want it running. You can geofence the plug to start circulating water when you are a half mile away from hole so you have hot water when you arrive. That way you aren’t moving water and running a pump while you are at work or away. Not only does it help in the winter but it provides almost instantaneous hot water to showers and sinks. Cost about $99 plus the smart plug if you go that route. SUPER SIMPLE AND PRACTICAL
Thanks. What if the pipe in not accessible and is PEX?
Crack open the that last fixture to a few drops per minute. Should keep the water flowing in the pipes. If you have a RO filter system make some filtered water and save it. The process will also flow the pipes in the late nite freeze. Do laundry late at night and run the drier to warm up the house and plumbing. The key is keep the water flowing when it gets below freezing.
Good advise.
No, no, no. That's just an act of desperation. Insulate properly, install heat tape where absolutely necessary and stop worrying. I live in central British Columbia, where it can drop to minus 40C. I've never had a frozen pipe in my home, because I insulated properly and completely eliminated air movement in my crawl space.
I live in Canada. We are using pex pipe to extend the garden hose far from the foundation of the home. We will insulate the pex pipe going outside of the house. Just wondering if it is enough to protect the pex pipe from freezing in -20 degree Celsius.
I have seen that type of heat tape caught on fire.
When we had our house built ten years ago, it didn't come across our minds to insulate all the pipes in our house, even after the fact we had a similar problem in our previous home. There was one winter where the pipes in the master bathroom sinks were frozen since they run along the outer wall.
Oof
Keep the heating on overnight when getting a beast from the east. That should prevent pipe freezes.
Attic ventilation is critical in hot climates. But when the air blowing thru your attic is zero degrees everything freezes. Oklahoma is cursed with 110 in summer, zero in winter. What to do?
best way to stop frozen pipes is to let faucet drip farthest away from where water comes in on the coldest days you are taking 50 degree water from the ground and slowly moving it through pipe and really cold spots will get warmer water from warm areas
This is the best how-to one yet!
Pipe tharring machine 😃
Gentlemen, I am very pleased with the information on that you have provided in this video. Thanks
Don’t trust heat tape. Just took mine out that came with the house and seen chard marks and melted insulation foam. I just went over kill insulating they pipes
That pipe insulation is not 100%. I have had pipes still freeze even with that on. I now tape the pipe up with insulation tape e.g. Shurtape IT100-2/30 IT-100, K-Flex, etc.. before putting the foam stuff on. Works every time.
good tips, thank you...
Insulation didn't work on mine, the frozen hot water pipe burst.
How to prevent frozen pipes. Move to SoCal.
Well, Richard is right if you have pipes that run trough an non-insulated garage or place in your house then THEY WILL FREEZE...how do I know ? because it has already happened in my house, the water leaked for an estimated 45 mins before a family came home and saw water everywhere (I was at work when i got the call ). The root cause was a pipe that ran from the 2nd floor kitchen to an non-insulated vestibule and after last week arctic temps and high winds the pipe froze and the Ice expanded enough to break the pipe. The wall where the pipe ran is now insulated and the basement is in progress of being refinished due to water damage, Yes Serv Pro did run their dehumidifier and blowers the dry the water but a couple electronic were damaged and all of the carpet and plaster need to be redone in the effected areas. If you work and your away from home for more than an hour and you live in a cold climate than turn your water off at the meter so just in case your pipes freeze there will be no additional water pressure from the street to accelerate the leak.
QuadroNVS I’ll save EVERYONE here some
Money with this. ridiculous methods!Freezeblock? Really? Sounds expensive. So. The solution is VERY VERY SIMPLE. Hot water recirculating pump. Installs at your water heater and you can even plug them into a smart plug to set a schedule for how often to recirculate warm/hot water because I don’t always want it running. You can geofence the plug to start circulating water when you are a half mile away from hole so you have hot water when you arrive. That way you aren’t moving water and running a pump while you are at work or away. Not only does it help in the winter but it provides almost instantaneous hot water to showers and sinks. Cost about $99 plus the smart plug if you go that route. SUPER SIMPLE AND PRACTICAL
Blippi
Insulation only keeps the heat in, hence the need for heat trace,
insulated pipes in my basement freeze just as well
I had one year in northern California my pipes froze at the water filter going into my house even the outside hose bib froze. Since I had a foot of snow on the ground I pulled out my propane heater and used it where I was working with a hair dryer. Between the two I had it thawed with no leaks in about an hour. I used heat tape with a thermostatic sensor and no freeze up since. My pipe heater instructions said to lay it on the pipe and secure it with zip ties. Then I sealed up the holes with expanding foam. I also made sure to wrap the pipe. To this day no more issues thankfully.
Hi George, what kind of insulation did you use over top of the heat tape? I've been reading that it should be fiberglass insulation in case there is a malfunction with the heat tape, i.e. fiberglass more resistant to catching fire than say a foam insulation. Thoughts?
Just let the faucet drip and it won’t freeze if water is slowly moving
Thanks so much
Armor flex is for refrigeration .you want the fiberglass insulation. Much better
Soffit vents are the problem in my house in Texas. The builders put the vents right in front of pipes which are run into exterior walls. Result frozen pex pipes! They are insulated but still freezing even with water on. My solution was to block attic vents nearest to pipes.
Any other solutions to help prevent frozen pipes?
I am 35 years old I'm renting my very 1st place I moved in a few hours ago I was wondering if I run cold water will my pipes freeze it's 20ﾟ outside I have oil heat I don't want to run hot water because I have a very small hot water tank if I run cold water through my pipes will they freeze or do I have to run hot water
I have cold water but no hot water
Hot water freezes faster than cold due to oxygen. Did it unthaw yet? If not take a heat gun or your hair dryer to the hot lines or use some space heaters. Then at night trickle hot water as well as cold if you can. Hope this helps. I live in a crappy trailer on a farm and it works for me, only problem I am having now is that my drain pipes to my kitchen and my shower are frozen so tomorrow I will be breaking pipe and either running a pump with hot water or antifreeze. Probably both. Damnit Minnesota!
Always keep a small trickle going if your pipes freeze and it should avoid the problem for the season.
Having watched it further don’t do any of it
They make foam elbows- I have em on my house - ???
Great Video !!! Thanks
Good Video,
But what about Thawing Pex?
i was going to ask about cpvc. they just assumed everyone has copper
Okay, it is easy to insulate lengths of pipes, but how do you insulate properly where there are lots of fittings and valves?
Foam tape, fiberglass insulation tape. Just wrap it around everywhere.
I put foam insulation sleeves on my residential copper pipes. It reduced the length of time to get hot water in the bathroom. A few years later I had collected from a few work snack days these empty giant mylar potato chip bags. I cut them open and sprayed them with vinegar water and wiped them down. I removed the foam insulation and cut the mylar into strips and wrapped the pipe, then replaced the foam sleeve insulation over it. This further reduced the time to get hot water but not as big. However the water is noticably hotter. My experience says get mylar lined foam if they have it or save your chip bags. Aluminum foil is metal and I don't think that will work like mylar.
Also I will mention you want to insulate the eight or twelve feet of cold water intake to the hot water heater. A lot of heat is lost this way and this will preheat water before it goes into the heater.
I’m trying to figure out is it worth to insulate the heater itself with heater blanket. I’m see yes and no on various channels. Please clarify
I live in Georgia and have old, plastic, brittle plumbing. I would like to know your opinion about putting pex in my attic. I live in a house that is on a slab and the plumbing runs inside the cement then through the walls. What a mess. My plumbing in my master bathroom as so many pipes running everywhere. Someone finally put a pex cold water pipe through the attic. I have never had leak. Now I am remodeling and I would like to replace all this plumbing. I know the less joint I have in the Pex is better to prevent freezing. What is your opinion before I start this project. Thank you for you video.
So....what if your pipes are frozen AND the electricity is out?
Here's what worked for us.
1) Keep all your faucets open
2) Find a neighbor who still has water
3) Fill up large buckets with their water and bring it to a boil on a gas stove (hopefully you have one and it still works)
4) When the water boils, pour it into large pots and place the pots near all potentially frozen pipes---under sinks, near washing machine, etc.
Don't forget the area where the water supply actually enters the house, wherever that may be. (Ours was near the water heater) This is a prime location where the freeze may occur
5) As the water cools, keep reboiling it and replacing the pots.
6) Repeat this for hours if necessary. (I know it's a pain. But it saved us big-time)
7) With any luck, water will begin to flow again.
👍❤️🩹 funny comments.
we used to use a welder to thaw frozen pipes, but now many people are using plastic pipe and the welder is useless, I use a heat gun a lot, the same one I use for removing paint.
Almost had hope with you mentioning pex (plastic) pipe. But then you said heat gun. Can't use a heat gun up into a closed wall.
Leave It Drip ! Peace/;-)))
He’s way off on those pipe sizes
How about talking about water faucet drip techniques?
I added that foam insulation after I had my 1st broken pipe to an outside faucet - - it was a mistake - it kept the cold in the pipe and it froze again -
What would you do about under a mobile home would you just insulate or use both heat cord and insulation
Can anyone advice , how to unfreeze the PEX pipe at farmhouse and how to prevent in the future?
Can’t use that pipe thawing machine with PEX 😢
PEX tends to resist ruptures in case of frozen water inside as opposed to metal or copper.
I have insulated all of my pipes but I still had issues. Installing the heat tape with the correct insulation this weekend. I live in two homes and its only an issue in extended below zero temps at my mt. home.
Scott Gibson I’ll save EVERYONE here some
Money with this. ridiculous methods!Freezeblock? Really? Sounds expensive. So. The solution is VERY VERY SIMPLE. Hot water recirculating pump. Installs at your water heater and you can even plug them into a smart plug to set a schedule for how often to recirculate warm/hot water because I don’t always want it running. You can geofence the plug to start circulating water when you are a half mile away from hole so you have hot water when you arrive. That way you aren’t moving water and running a pump while you are at work or away. Not only does it help in the winter but it provides almost instantaneous hot water to showers and sinks. Cost about $99 plus the smart plug if you go that route. SUPER SIMPLE AND PRACTICAL
Travis Tuell Thanks I will look into it. The problem is the pipe that is freezing is before my hot water tank. The tape is inexpensive, about 37.00 including the insulation. I only have the issue when we get sustained negative temps. Take care
Hi Scott, what kind of insulation did you use over the heat tape? Thanks - Peter
It's much easier to just install a Hot Water Lobster instant Hot Water Valve.
What is a Hot Water Lobster?
Great tip on the pipe thawing machine, but doubt it will work on pex. What next??
PEX can expand more and resist rupture.
I replaced my faucet bib outside for a PEX one, definitely worth it, the rest of my pipes are inside and keep my house at 62 degrees, with my hydronic baseboards.
you have to use heat tape in a mobile home with skirting with the foam insulation
Or,leave the water running a pinch on those cold nights and it won't freeze at all. Always go to the farthest outlet from the main supply into the house to leave open
Thanks
Seems to be the problem right now in Texas with pipes outside along house not protected
Good to know it got down to 17F and lower today
Will that clamp pipe thawer work on plastic pipes?
how about to thaw or keep drains were freezing ?
I live in Chicago and have an issue with frozen city water pipes outside underground. Apparently, the frost line has penetrated deep enough to surround the water main coming to my house. I forgot to drip a faucet one night and the next morning I have no water. Now I can only wait for the city to resolve the issue. Today is Day 5.
racist
please read the instructions on the heat cables. the ones I have seen don't recommend wrapping the cable around the pipe but, lay it flat against and use a tape or nylon wire ties.
exactly, I see many heat tapes that are supposed to be laid flat and taped every six inches wrapped around the pipe and also wrapped around its self, A fire waiting to happen
Look at the type of cable you want to buy. You are probably referring to a constant wattage cable, which should not be overlapped. However, a self-regulating cable, such as a Raychem Frostguard, can be wrapped around a pipe, overlapped and insulated without any danger. The cable reduces power where the temperature rises, such as an overlap.
I'd like to know if letting my water run at a small steady stream all night will prevent my pipes (pvc, I think) from freezing without damaging my well pump? I have a drilled well that's 220 Ft deep with a submersible pump. I don't think leaving a tiny stream running in 2 faucets should run the well dry since I used to leave the water hose slightly spraying sometimes 24/7 for the birds and other animals. I have a 300 Watt Halogen work lamp under my home where the poorly-insulated water lines come out of the ground so I think that helps but we are having unusually low temperatures (down in the teens) in the Atlanta area this entire week and I can't afford a disaster. So will letting my water run prevent freezing pipes without damaging my well pump? Thanks to anyone for advice.
Refering to adding light to the water pump my Grandfather used a 100 watt light bulb against the water pump and kept it on during the winter there was no frozen water line.
Warren Thomas. Thanks! That's comforting to know. My pump is submerged but the water line that's coming up out of the ground about 4 ft to my floor isn't very well insulated (it "was" wrapped but it came off last year and I failed to check it). I have the lamp on a cinder block near the pipe and I secured the underpinning panel as best as I could. So... I suppose if a regular 100 Watt bulb prevents freezing, I should be set! ☺ (well, as long as critters don't knock my lamp over and blow the bulb - LOL!) Anyway, thanks again and stay warm! ☺☺☺
tammygurl64 I’ll save EVERYONE here some
Money with this. ridiculous methods!Freezeblock? Really? Sounds expensive. So. The solution is VERY VERY SIMPLE. Hot water recirculating pump. Installs at your water heater and you can even plug them into a smart plug to set a schedule for how often to recirculate warm/hot water because I don’t always want it running. You can geofence the plug to start circulating water when you are a half mile away from hole so you have hot water when you arrive. That way you aren’t moving water and running a pump while you are at work or away. Not only does it help in the winter but it provides almost instantaneous hot water to showers and sinks. Cost about $99 plus the smart plug if you go that route. SUPER SIMPLE AND PRACTICAL
Travis Tuell. Thanks for your recommendation. It's ironic I was thinking about the hot water pipes providing warmth to the cold water pipes the other night when I was using hot water intermittently all night. Your product sounds great for people with easy access to their hot water heaters but it's not for me. I've had multiple disasters with my hot water heater which is in an almost inaccessible location in the back of my closet so the last thing I would want to do is have something connected to it that could at some point cause nightmarish problems for me. Besides... so far, my 300W halogen worklamp has done it's job and it only cost me $8.99. I do appreciate your taking the time to respond though and will keep it in mind for others who may be interested. Best wishes to you! ☺
tammygurl64 you can install the pump on Any water line in the house. Under a sink etc. doesn’t have to be at water heater. Water heater location is just more convenient for most
Super great video
I always thought in the winter if you don't have heat in your house your pipes can burst
Of course they can. You are living in your house, aren't you? You'll have the heat on.
HOW DO YOU DO THIS WHEN THE PIPES ARE IN AN ATTIC AND VIRTUALLY INACCESSIBLE, LIKE IN MY HOUSE,
which I INHERITED, did not buy, and had no choice in its lousy design?
The Ultimate Reductionist add a thermometer and make sure you keep it above 32 degrees.
Heat the attic
Heat tracing
What about PEX? Will that freeze? Will it? Huh? Huh?
alex tworkowski yes it will but wont break
That's what I suspected. Thank you.
You ask like a douchebag. Yes it will but it's made to go back to it's original shape but like your mom it can only be stretched out so many times before it loses its form and once that happens expect a crack.
@@tgetty18 😂
@@angelicavilla8154 Wrong. PEX can freeze AND crack. Mine did that a few days ago.
Good information vibration 👍😎
Oil line froze up on me put the heat tape and insulation worked like a charm
I got a tip use plastic
If leaving faucets to drip as a preventative method, how many faucets in your house should be left dripping?
Brian Miller all the ones that may experience below freezing temperatures. Or just one, to keep the line from freezing.
The one on the highest floor.
HOW TO TEST PIPE HEAT CABLE TO KNOW IT ITS STILL WORKING UNDER MY MOBILE HOME .i HAVE A FOAM INSULATING PIPE COVER OVER THE HEAT CABLE. SHOULD i FEEL THE PLUG WITH THE FIRST FOOT OF CABLE GETTING WARM IF IT WERE 38 DEGREES OUTSIDE?
Rondo Schiavoni t
The heat tape I had years ago had a light near the plug and when that light quit working so did the heat tape. I never replaced mine but sure wish I had!
I don't like the fact that it is standard practice of builders to leave pipes exposed to cold in an uninsulated wall. That is lawsuit stuff if you ask me. Too bad the building was done years ago and can't be sued for, because everyone who does that should deal with it, not the person who trusted a builder. It's way beyond irritating and violates common sense. Was there a shortage of insulation at some time? Just maddening.
Wrap insulation does not make a pipe warm, it's a heat transfer retardant . The only difference between a wrapped pipe and one with no insulation freezing is about 1 1/2 hours to freeze. See www.freezeblocker.com to do it right!
That's a very astute observation that most people would not think of. Left for extended periods of time, the temperature of the wrapped pipe will sink to ambient and the water in it will freeze.
I agree. Had a sprinkler pipe break in the attic of our office condo. Insurance company laughed when they saw wrap insulation as our method of freeze protection. TOH should update this episode with the www.freezeblocker.com solution!
alex tworkowski the only difference between a wrapped cold, no flowing water pipe and one that’s not wrapped is about an hour and a half till fully frozen.
Don't you think the R value of the insulation makes any difference?
alex tworkowski it only delays the time until its frozen .
This guy doesnt know what he is doing, he said last resort put heat tape on pipes... if you lived in a area 6 months out of the year were it's 26 and -10 degrees you don't want to take this man's advice you must use heat tape and insulate your pipes 100%
What kind of insulation do you use over top of the heat tape? Does it need to be fiberglass insulation to reduce fire hazard in the event there is a malfunction with the heat tape? Thoughts? Thanks - Peter
Right. So. You're that last resort
I must of missed your TV Show - what channel and time are you on?
insulating the pipe in cold country without a heat tape under it is a waste of time..
dave12546 o
dave12546
Some plumbers have told me that heat tape could start a fire.
That's a fire hazard. A better option would be to tape up the pipe with something like Shurtape IT100 or K-Flex before putting on the pipe insulation.
That's only if the wire isn't grounded properly. Heat traces usually have 3 wires going to it.
Great Info!!
Should I turn off the water main
seanpierpont no, that'll make it worse. You would have to drain all the water which may be difficult. Either heat the space and/or pipe or keep it dripping during coldspells.
Yes, and drain the pipes by opening the lowest faucet in the house. Stock up on water first. What these people are talking about is for a situation where you have power and the cold is shirt term. For long term and power outage like in Texas lately, I would have (and did) turn off the water and drain the pipes. Mine were fine. I see no other way to face the texas power outage
@@mitchjohnson4714 yea I turn them on if it says 20 or below for more than a day ...I put insulation on All pipes so in the future that will help me too. Thanks.
Love how they talk down to people "or you could insulate properly" sorry bucko but most people just buy a house and it's done you have ZERO say in what was done when it was built and even building a house you have to be on top of the builder to make sure things are done right and most people don't have that sort of time.
Using foam insulation alone is NOT going to keep the pipes from freezing when the water sits idle in the pipe for any extended period of time (depending on how low the temperature gets). Yet more bad advise from this clown!
Just let your faucets drip all night and you will avoid freezes.
That's a patch not a fix
I now know how to “thar” a frozen pipe. Gonna keep searching to learn how to thaw one.
0:27 Richard predicting the flooded houses in Texas during Feb 2021.
Every building has its own situation depending on how it was built.
There is NO one way to stop pipes from freezing.
Leaving a faucet dripping in the 2nd floor doesn't mean the water supply for the w/c on the 1st floor won't freeze. It all depends on where and how the pipes were layed out.
And FYI, using a hair dryer or heater under a kitchen cabinet or vanity almost never thaws a frozen pipe. those areas tend to be warm, pipes freeze in cold locations usually on exterior walls, in between the studs that are pourly or insulated wrong.
But please UA-cam keep giving homeowners wrong info so I can keep thawing pipe!!!
I've got one way that will fix it all. Turn off the water supply and drain the pipes until you can maintain the pipes above freezing temperatures.