Excellent presentation....I spent almost 50 years as a carpenter/contractor and finally a superintendent for one of the larger contractors in my state...that said, I know that many of the methods we we began using at start of the constructions trades awareness of energy and it's real costs in the early 70's (this was really triggered by the oil embargo) failed outright or caused costly repair work years later...I'm preparing to build what will by my last home for my wife and myself and really appreciate the effort that many professionals are taking to educate the building trades as to what are proven "best practices"....Thanks for your effort to educate us all....
Thank you for talking about volatile chemical off-gassing, chemicals slowly escaping from the foam as the chemical reactions that solidified it subside. For volatiles to be below the odor threshold, too dilute to smell, is not an adequate safety criteria. How long volatiles off-gas, and what their concentrations in the air over time are, determines the risk of cancer or other potential diseases. We need quantitative measurements of compounds per cc of air, over time, and the technology for doing that is available, inexpensive, and straightforward to employ. It’s not adequate to use measures like “a long time before” as a guide to what is safe. It’s a big improvement however - thank you, over ignoring the existence of the risk. I usually look to California to do the right thing first in areas like this. But their nice climate means they’ll see less spray foam. So, Massachusetts, time to kick in, please!?
We see a lot of spray foam for California homes that have a more contemporary design and a variety of other design reasons. Drier climate zones also are more forgiving of insulation installation problems. I think it's still up to the builders to use qualified installers, to understand proper installation themselves, and find the better products--despite the regulations.
Can you fill me in on what tech is available to test the long term air quality in spray foamed homes. The only thing I could find was a local lab at a cost of $3700 to test my air for the chemicals in spray foam
Starting an addition this week with a crawl space and I had to argue with the township they wanted it vented to outside. I’m doing a conditioned crawl space with concrete floor and it will be like you said a mini basement open to the original basement. It surprises me that some areas still don’t get it and you have too explain the science
Great videos but I wish they would state what climate zones they are referring to more often. I’m not sure if this applies to our desert house or not. So far I’m please with the house. It does not seem to need the complicated systems of cold climate or humid climate houses. We need more cooling than heating. The crawlspace has foam on the outside of the foundation. That’s probably good here as the ground heats up a lot in summer. The venting is only a few small 1/2” holes drilled on one side and a 4” vent on the other side. Ive only noticed a little humidity in summer for 2 months during monsoon season. I don’t think that little humidity will pose a problem and might be good here. Ive not seen a drop of water on the gravel floor. Wish it was slab and a full basement. Need the cool space. It’s important to check once a month for leaks under a house. Listen if the pump is running more than it should be.
Have always called my 1972 rancher crawl space "hell" at least it started with a skim coat of concrete and not open dirt. On the Wet Coast of Canada it is unfortunate they did not understand or were to cheap to do our "hells" properly. Have had mine for twenty five years and has been a work in progress, now have to replace the pony wall siding as the rot has gotten it. Recently saw a guy using flex seal and at three years is still good. Would be nice to seal the skim coat to help stop moisture migration. But will never get my money or effort worth as when we sell it will be a knock down for redevelopment.
Hi! Thank you for your video! I have a few quick questions... Would we use the poly-iso with the radiant paper on it, or without? Also, what should be used to attach the poly-iso to the stem wall? Liquid nails? Then we would tape a plastic barrier to the poly-iso to cover the ground, so how thick does the plastic need to be, 10 mil or higher? Questions are for climate zone 3 in NE Oklahoma. Bathroom remodel project. In the process of raking out the ground to make it nice and even under the floor and prepare for either insulating under the floor or encapsulating the entire space.
Hey! Great video! I'm trying to design a shed with a Float Tank for my dad, who was in a hit and run accident 20 years ago, after which he hasn't been able to sleep well. Do you know of a place where I could be around like-minded people who I'd be able to bounce my ideas off? I'm a mechanical drafter, so I have very limited know-how when it comes to that stuff.
How would you best insulate under living space that is not inclosed? What first did was 2" xps cut to joist bays the air seal that with closed cell foam to fill gaps. I then put 4" roxsol to finish. I put 1/2" chicken wire as a coverall to keep mice out.
I’m working on a log cabin that was insulated under the floor joists that contributed to the rim joists needing to be completely replaced around the perimeter stem wall foundation. I’ll be lifting the house up to replace the rim joists. The log construction is leaky by nature and even if I follow your instructions to the Tee, the log walls still allow moisture to migrate behind the logs and down to the rim joist. I’d love to see a detail on how to mitigate this issue. Any suggestions ? - thank you for your book! - Jay Dawes
When you say "insulating a crawl space" I hear it differently, I think you mean insulating a raised floor. If someone says to me, "We want to insulate the crawl space." I assume they want the crawl space insulated, not the floor. I like the assemblies you show! Yet, none of them look like the pictures you show with the membrane visible on all surfaces. We use spray foam in many buildings, no problems. On a side note, my own crawl space (ca 1980), too shallow, not well insulated, subject to ground water, does not look bad really with wood holding up nicely etc. The old metal piers are another matter!
The longterm durability of below grade rigid insulation is a MAJOR concern. While it's not impossible to provide a protection course, bugs love to burrow into below grade insulation, especially if it's wet. I'll gladly sacrifice a few extra Btus if it means I'll get significantly better longterm durability.
@@ASIRIDesigns I am pretty sure if you put modern waterproofing membranes over rigid Rockwood, you will have a near permanent solution. Doubtful that critters will gnaw into it. Also run a WUFI on the internal solution and see how it pans out over time. You want the thermal Mass of the foundation protected from the exterior climate. But I am biased because I also use a continuous exterior insulation on walls and roof as well.
Exactly. Also try convincing your termite pest control company insulating the crawl space wall is a good idea, even with an inspection gap. Meanwhile, let's build up radon gasses, soil gasses, and just ignore the "V" part of HVAC. Let's just trash the IAQ. Videos like these are only 70% of the required solution. Where's the ventilation? And, why do these videos ignore or gloss over stack effect? No one to my satisfaction has a total solution, not even Lstiburek. And in 2024, builders have thus thrown their hands up in the air and build on slab. All of it is crap. Every 30 years, you have to practically rebuild 1/2 your home. It's no wonder 169,668 or 48% of the households in Charlotte, NC are renter-occupied while 184,774 or 52% are owner-occupied.
Excellent presentation....I spent almost 50 years as a carpenter/contractor and finally a superintendent for one of the larger contractors in my state...that said, I know that many of the methods we we began using at start of the constructions trades awareness of energy and it's real costs in the early 70's (this was really triggered by the oil embargo) failed outright or caused costly repair work years later...I'm preparing to build what will by my last home for my wife and myself and really appreciate the effort that many professionals are taking to educate the building trades as to what are proven "best practices"....Thanks for your effort to educate us all....
Thank you for talking about volatile chemical off-gassing, chemicals slowly escaping from the foam as the chemical reactions that solidified it subside. For volatiles to be below the odor threshold, too dilute to smell, is not an adequate safety criteria. How long volatiles off-gas, and what their concentrations in the air over time are, determines the risk of cancer or other potential diseases. We need quantitative measurements of compounds per cc of air, over time, and the technology for doing that is available, inexpensive, and straightforward to employ. It’s not adequate to use measures like “a long time before” as a guide to what is safe. It’s a big improvement however - thank you, over ignoring the existence of the risk. I usually look to California to do the right thing first in areas like this. But their nice climate means they’ll see less spray foam. So, Massachusetts, time to kick in, please!?
We see a lot of spray foam for California homes that have a more contemporary design and a variety of other design reasons. Drier climate zones also are more forgiving of insulation installation problems. I think it's still up to the builders to use qualified installers, to understand proper installation themselves, and find the better products--despite the regulations.
Hu... I wonder if an ozone generator would be able to cut down the time it offgasses.
Not related to the subject but I wonder how many people realize your UA-cam name is SOS in Morse Code 😊
Can you fill me in on what tech is available to test the long term air quality in spray foamed homes. The only thing I could find was a local lab at a cost of $3700 to test my air for the chemicals in spray foam
Starting an addition this week with a crawl space and I had to argue with the township they wanted it vented to outside. I’m doing a conditioned crawl space with concrete floor and it will be like you said a mini basement open to the original basement. It surprises me that some areas still don’t get it and you have too explain the science
Your channel is quite great, good resource for building science knowledge hungry people.
Great videos but I wish they would state what climate zones they are referring to more often. I’m not sure if this applies to our desert house or not. So far I’m please with the house. It does not seem to need the complicated systems of cold climate or humid climate houses. We need more cooling than heating. The crawlspace has foam on the outside of the foundation. That’s probably good here as the ground heats up a lot in summer. The venting is only a few small 1/2” holes drilled on one side and a 4” vent on the other side. Ive only noticed a little humidity in summer for 2 months during monsoon season. I don’t think that little humidity will pose a problem and might be good here. Ive not seen a drop of water on the gravel floor. Wish it was slab and a full basement. Need the cool space. It’s important to check once a month for leaks under a house. Listen if the pump is running more than it should be.
Have always called my 1972 rancher crawl space "hell" at least it started with a skim coat of concrete and not open dirt. On the Wet Coast of Canada it is unfortunate they did not understand or were to cheap to do our "hells" properly. Have had mine for twenty five years and has been a work in progress, now have to replace the pony wall siding as the rot has gotten it. Recently saw a guy using flex seal and at three years is still good. Would be nice to seal the skim coat to help stop moisture migration. But will never get my money or effort worth as when we sell it will be a knock down for redevelopment.
In my area, code requires a 4" termite inspection gap between the top or the concrete and bottom plate. Is there any work around for this?
Hi! Thank you for your video! I have a few quick questions... Would we use the poly-iso with the radiant paper on it, or without? Also, what should be used to attach the poly-iso to the stem wall? Liquid nails? Then we would tape a plastic barrier to the poly-iso to cover the ground, so how thick does the plastic need to be, 10 mil or higher? Questions are for climate zone 3 in NE Oklahoma. Bathroom remodel project. In the process of raking out the ground to make it nice and even under the floor and prepare for either insulating under the floor or encapsulating the entire space.
Hey! Great video! I'm trying to design a shed with a Float Tank for my dad, who was in a hit and run accident 20 years ago, after which he hasn't been able to sleep well.
Do you know of a place where I could be around like-minded people who I'd be able to bounce my ideas off? I'm a mechanical drafter, so I have very limited know-how when it comes to that stuff.
How would you best insulate under living space that is not inclosed? What first did was 2" xps cut to joist bays the air seal that with closed cell foam to fill gaps. I then put 4" roxsol to finish. I put 1/2" chicken wire as a coverall to keep mice out.
I’m working on a log cabin that was insulated under the floor joists that contributed to the rim joists needing to be completely replaced around the perimeter stem wall foundation. I’ll be lifting the house up to replace the rim joists. The log construction is leaky by nature and even if I follow your instructions to the Tee, the log walls still allow moisture to migrate behind the logs and down to the rim joist. I’d love to see a detail on how to mitigate this issue. Any suggestions ? - thank you for your book! - Jay Dawes
approximately how long does the clothes spray foam take to off gas? are you talking about one week three weeks month?
When you say "insulating a crawl space" I hear it differently, I think you mean insulating a raised floor. If someone says to me, "We want to insulate the crawl space." I assume they want the crawl space insulated, not the floor. I like the assemblies you show! Yet, none of them look like the pictures you show with the membrane visible on all surfaces. We use spray foam in many buildings, no problems. On a side note, my own crawl space (ca 1980), too shallow, not well insulated, subject to ground water, does not look bad really with wood holding up nicely etc. The old metal piers are another matter!
What does long before the occupants move in mean?
I sure wish that whoever built my house a hundred years ago had watched this video first ;-)
Insulation on the inside of the stem wall is incorrect. Insulation should always go to the exterior. Where do you wear your coat ?
The longterm durability of below grade rigid insulation is a MAJOR concern. While it's not impossible to provide a protection course, bugs love to burrow into below grade insulation, especially if it's wet. I'll gladly sacrifice a few extra Btus if it means I'll get significantly better longterm durability.
@@ASIRIDesigns I am pretty sure if you put modern waterproofing membranes over rigid Rockwood, you will have a near permanent solution. Doubtful that critters will gnaw into it. Also run a WUFI on the internal solution and see how it pans out over time. You want the thermal Mass of the foundation protected from the exterior climate. But I am biased because I also use a continuous exterior insulation on walls and roof as well.
Sounds like utopian, but good luck tryn to convince FEMA, insurance, and most inspectors its a good idea to remove vents..😂
You do realize that the 2018 IRC gives a code approved unvented craw-space option? R408.3 Unvented crawl space.
Exactly. Also try convincing your termite pest control company insulating the crawl space wall is a good idea, even with an inspection gap. Meanwhile, let's build up radon gasses, soil gasses, and just ignore the "V" part of HVAC. Let's just trash the IAQ. Videos like these are only 70% of the required solution. Where's the ventilation? And, why do these videos ignore or gloss over stack effect? No one to my satisfaction has a total solution, not even Lstiburek. And in 2024, builders have thus thrown their hands up in the air and build on slab. All of it is crap. Every 30 years, you have to practically rebuild 1/2 your home. It's no wonder 169,668 or 48% of the households in Charlotte, NC are renter-occupied while 184,774 or 52% are owner-occupied.