spray foam insulation, is it safe?

[diwit]

help!

we live in an OLD home, built in 1905. it's sitting on a crawl space. currently, the only insulation underneath is the panels of rolled insulation, but it is taking on moisture and falling.

we have had an energy audit, and the company is recommending a spray foam insulation (in combination w/ putting down plastic on the floor of the crawlspace), to be applied to the "ceiling" of the crawlspace.

MY CONCERN: this spray foam IS chemicals. the company says they are using the best, least toxic product they can find, and that off-gassing is only a few days. online i've read that some people have had to move out b/c of fumes that last months.

so, i'm very worried that this is our only viable option (we NEED some insulation there, and what we have now is only inviting mold), but it is not good at all.

any experience/wisdom/ideas?

thank you!

 

[WOODY2]

Ask them to provide contact info for recent like installs?

 

[emulous74]

The chemicals are combined when they are installing/spraying it. You must use someone that is certified in this. If they don't know what they are doing, then you will get lethal off-gassing. My suggestion is go with closed-cell spray foam in the crawl space since you have moisture. Open-Cell spray foam acts like a sponge, where closed-cell doesn't let water/moisture through. One of my houses is insulated with Open-Cell spray foam. I run an Airthings "View Plus" Monitor in all my houses it monitors Radon, PM 2.5, Co2, Humidity, Temp, VOC and Pressure. In the house that is spray foamed I get under 1 in VOC and no static PM 2.5, only shows PM 2.5 when cooking or have the windows open.

Moral of the story, it can be done very safely, but the installer has to know what they are doing to make it so. I wouldn't hire anyone to install it if they don't have a guarantee for air quality (might be hard to measure if you are only doing the crawlspace, but they can take a before and after so you can prove the air quality got worse after they sprayed. I would also suggest no one is around for 3 days after it's been done and do the air quality test before you move back in.

 

[NatersXJ6]

Individuals have very different thresholds of detection for these sorts of things. If you’re asking about it, I would imagine you are at risk for noticing the odor long after most people have forgotten it. Testing will tell you if it is safe against NIOSH or similar standards, but if you or a significant other smell it you will have issues. I suggest going to visit a place where your contractor recently applied it and decide for yourself. Personally, I’ve spent a lot of time working in industrial Health / Safety and I wouldn’t blink an eye when considering spray foam in my house with my family. Better to have small amounts of known chemistry than annual assaults of molds and mildew and cold.

 

[simple]

If you have old plumbing or electrical that may be an issue in foreseeable future it might be worth updating it. Once the foam is in, it will be cast around all that stuff and make it difficult to access.

 

[AbleGuy]

We lived in a similar house in a wet climate…it too was built in early, early 1900’s, had the crawl space and an unvented foundation, no floor insulation.

To control moisture issues, I cut into the bottom of the siding at the end of the floor joists and installed numerous foundation vents and put a thick, well fitted vapor barrier down over the moist soil beneath the house. These proved very effective .

It seems like you have two challenges: controlling the moisture, and effectively insulating your floors. That excessive moisture can get drawn out of the soil and into your house, especially from winter home heating, soaking the batts of underfloor insulation (making them less efficient).

You might consider adding the foundation vents when you install the vapor barrier.

 

[calicamper]

We lived in a similar house in a wet climate…it too was built in early, early 1900’s, had the crawl space and an unvented foundation, no floor insulation.

To control moisture issues, I cut into the siding and installed numerous foundation vents and put a thick, well fitted vapor barrier down over the moist soil beneath the house. These proved very effective .

It seems like you have two challenges, controlling the moisture, and effectively insulating your floors. That excessive moisture can get drawn out of the soil and into your house, especially from winter home heating, soaking the batts of underfloor insulation (making them less efficient).

You might consider adding the foundation vents when you install the vapor barrier.

Have done the same in one of my properties. 3mm plastic rolled out/ pinned down under the house. Hill side 6ft deep french drain system across the back and down the side. Massive difference totally addressed the major moisture issues. 👍 not cheap but was worth it

 

[simple]

I had 2 houses that were built over a drained bog. The geo underneath them was saturated peet and both houses had a ton of standing water under them. After a lot of head scratching I pumped controlled density fill under them. The fill sets up similar to concrete so I used a screed and sloped it all to one end of the foundation. One house I was able install a drain to daylight at the low end. The other one I installed a sump pump. That system worked perfectly.

Controlled density fill was good because it's porous and if water found its way to the top of it, it would run to the drain and anywhere else it would perk back down through the slab.

Prior to the fill solution I trenched around the outside of the foundation and put in perf pipe and drain rock that all sloped to day light but it didn't help the situation. Ground water still came up on the inside of the foundation.

 

[AbleGuy]

I had 2 houses that were built over a drained bog. The geo underneath them was saturated peet and both houses had a ton of standing water under them. After a lot of head scratching I pumped controlled density fill under them. The fill sets up similar to concrete so I used a screed and sloped it all to one end of the foundation. One house I was able install a drain to daylight at the low end. The other one I installed a sump pump. That system worked perfectly.

Controlled density fill was good because it's porous and if water found its way to the top of it, it would run to the drain and anywhere else it would perk back down through the slab.

Prior to the fill solution I trenched around the outside of the foundation and put in perf pipe and drain rock that all sloped to day light but it didn't help the situation. Ground water still came up on the inside of the foundation.

Great idea to mention the sump pump. 👍🏻

They’re useful and very effective in areas where you have an over abundance of water in the soil below your house, get lots of heavy rain or snow and have drainage slope problems.

The reference by CC ⬆️ of using an exterior French drain is also good advice.

Solving the water problem before fixing the insulation issue sounds like the way to go here.

 

[diwit]

The chemicals are combined when they are installing/spraying it. You must use someone that is certified in this. If they don't know what they are doing, then you will get lethal off-gassing. My suggestion is go with closed-cell spray foam in the crawl space since you have moisture. Open-Cell spray foam acts like a sponge, where closed-cell doesn't let water/moisture through. One of my houses is insulated with Open-Cell spray foam. I run an Airthings "View Plus" Monitor in all my houses it monitors Radon, PM 2.5, Co2, Humidity, Temp, VOC and Pressure. In the house that is spray foamed I get under 1 in VOC and no static PM 2.5, only shows PM 2.5 when cooking or have the windows open.

Moral of the story, it can be done very safely, but the installer has to know what they are doing to make it so. I wouldn't hire anyone to install it if they don't have a guarantee for air quality (might be hard to measure if you are only doing the crawlspace spray foam insulation washington dc, but they can take a before and after so you can prove the air quality got worse after they sprayed. I would also suggest no one is around for 3 days after it's been done and do the air quality test before you move back in.

thank you so much for your suggestion

 

[IdaSHO]

Spray foam certainly has its place, and has become more and more common with regions that require a "blower door test" for whatever reason, as it functions as serious air barrier.

That said, and as a builder, I use it sparingly. Depending upon your climate, a "tight" house like a spray foam house is so tight that if not built correctly, it quickly becomes a health hazard. Built that tight, moisture simply causes problems, if not dealt with correctly. The oldest stick frame buildings on the planet are full of leaks, and they remain standing because of those leaks. If moisture gets in, it must find a way out. And be sure you know which foam you are getting involved with, be it open cell or closed cell. Both have their places, but both can also lead to problems.

In North Idaho, the winters and average ambient moisture content makes spray foam a bit of a liability, so traditional insulation is still the most commonly used.

A recent build, one I designed and built for my parents to retire in, uses a combination of traditional fiberglass batt w/ kraft face and closed cell spray foam.
Reason being.... the "attic" of this home was designed from the beginning to be a conditioned space, and provide the room to house HVAC equipment. So the roof deck, galble ends, and a few other locations received closed cell spray foam. The big walk out bay window received it as well, as there was just enough material to do so. The rest of the home received good old fiberglass (actually glass wool) insulation.

A few photos... and for those wondering, the studs are a full 16' long, and highest point in the vaulted ceiling is 23' tall as I recall.

And after sheetrock, texture, and paint

 

[calicamper]

There is a new system for closing up air leaks in houses can be done in older homes. Pretty awesome technology and really not that complicated.

 

[AbleGuy]

There is a new system for closing up air leaks in houses can be done in older homes. Pretty awesome technology…

Well, if our use of a gas water heater, a gas cook stove and a gas furnace now supposedly means “dangerously unhealthy” air inside the house, we’ll happily stick with an old, drafty home with old single pane leaky windows and doors. 😎

(Oddly enough, the most air tight home we’ve lived in [per tests done by the local utility company] was our last place in Montana, built into a rocky hillside, where radon off gassing into homes was the killer! (Fix A, break B).

 

[IdaSHO]

Thats a good point, radon is an issue in North Idaho as well.

Building a less tight home is cheaper and more simple in many way. But efficiency pencil pushers have been challenging the overall envelope of homes for years. So things like air exchangers/handlers, triple pane windows, thermal breaks via ridged insulation, etc…. are now commonplace.

Building science has advanced a ton, but in general it costs a great deal more and is more complicated as a whole. And builders in general simply cannot manage such complication. The average stateside builder is an absolute hack when compared to other countries.

 

[emulous74]

Scientifically an Air-Tight house is the desired result. You should control what air comes into and out of the house. A house is a system you can choose whether it's passive or active. The two camps seem to be at opposing sides in this, but actually both sides are correct in specific situations. On the breathability or loose house, you can't control the humidity or air quality of the air coming into the house, but that uncontrollable air allows the wood in the house to dry out, that is the only reason a loose house is deemed good. However, with science and update in building codes (which are very lacking in the US) today's builders can and should build an air and water tight house, using rain screens and air gaps between the water/airtight sheathing so whichever siding is chosen can dry from the front and the back. Once you do this, then as current code requires, you must bring fresh air into the house, this can then be controlled by an ERV/HRV, filtration and de-humidification. In order to get bad air out of the house, you just have to have balanced system that provides make-up air when an exhaust fan or the such is turned on.

I'd much rather be able to control and alter the air coming into my house, rather than leaving it up to chance.