Spray foam insulation

STEAM DOCTOR

National Grid (gas supplier) is offering free foam insulation. Before I take the leap, what are the pros and cons? I know this issue has been discussed here before. Fwiw, I have an attic that I would like to renovate at some point There is currently fiberglass in in-between the floor joists. Attic walls and roof is not insulated. As far as I can tell, the house walls are not insulated (unless you count the foam board that was added when the new siding was added). I belief that I have balloon framing but not certain about that and might vary in different parts of the house. The walls are all old plaster as far as I can tell. Thanks in advance any input. 

HomerJSmith

What type of foam? Urethane at one time had out gassing, not good for your health.

STEAM DOCTOR

@HomerJSmith Will try to find out.  The gassing was during the installation process or after?

HomerJSmith

It was the product of decomposition. Installation, during curing, too.

Larry Weingarten

Hi, Here’s this: https://archive.epa.gov/epa/saferchoice/health-concerns-about-spray-polyurethane-foam.html
I heard a talk from a man who was made quite sick and ultimately had to have his house torn down after spray foam was used to insulate it. The job was done by a reputable contractor and inspected by the manufacturer. I use foam board and caulking or blown in cellulose.

Yours, Larry

jumper

Decades ago Canadian government paid for homeowners to spray in urea formaldehyde aka UFFI. Then it paid for removal. Panic was that it outgassed formaldehyde, which somehow supposedly stayed indoors. Turned out to be bs but nobody does UFFI anymore. If there was an issue it was that UFFI sealed too well and then gas from all sorts of products increase concentration of formaldehyde. I guess Canadians never opened doors or windows? Since the nineties Canadian houses are built tight and come with energy recovery ventilators. Don't know if fuel savings offset electricity for ERV.

Jamie Hall

There's spray foam and spray foam. Stay away from anything resembling urea formaldehyde -- if it's even still available. Open cell polyurethane (such as Icynene) work quite well -- and, being open cell, are not quite so prone to rot problems if the exterior envelope isn't kept tight. I've used it on the underside of an attic roof and in a few other places.

That said, you mention plaster. All spray foams expand as they cure -- that's why they seal so well. Unhappily, that can pop the keys on the plaster, resulting in damage to the interior walls which can be really expensive to repair. If you were to go that route, get a written guarantee from the installer that that won't happen, or if it does happen they will repair the damage IN KIND (that is, real plaster -- not drywall).

JakeCK

I've heard of horror stories of where it had to be removed by very aggressive means. One such story was where the entire roof had to be demolished and rebuilt from the top of bedroom walls up. But everything I have heard indicates the problem occurs when the temperature and/or mix isn't right. Such as a too cold or too hot attic or tanks, bad spray gun, clogged nozzle, etc. Basically it is a chemistry experiment in your home, and if it goes sideways it doesn't cure right. Done well you end up with a very well insulated tight house. Done badly and the smell alone can make you nauseated.

At work we some times receive equipment parts packed in crates with foam sprayed into a plastic bag like thing around the parts to protect them. Most of the time the stuff is fine, just a light smell if you break a piece in half. But every once in a while you'll get some that you know immediately something didn't cure right. Some years back I took chunks of some particularly smelly foam and stuck them in a few trash cans by the desks of a few coworkers. I had a good laugh while they tried to track down the smell. It almost smells like dead fish... It really is weird. 

STEAM DOCTOR

Will try and contact some installers tomorrow and will try to get some info. Non health related. Do I need to be concerned about roof leaks? Meaning, what happens if roof develops a leak? Is the foam waterproof/resistant? Will water sit on top of foam and rot out the wood??

Jamie Hall

Closed cell foam is a real problem with roof leaks, as it will trap the water. Open cell is much less of a problem -- but a big leak would still be a problem. If the roof is in good shape and kept that way, not to worry. Much...

ChrisJ

I've used "great stuff" in a few areas where it was difficult to access and I needed a near perfect seal. For example around ductwork coming down from the attic.

Most of it got sealed using just caulk but there were two ducts that needed spray foam for various reasons.

The smell was always tolerable but we're talking a very tiny amount compared to doing a whole house.

JakeCK

ChrisJ said:

I've used "great stuff" in a few areas where it was difficult to access and I needed a near perfect seal. For example around ductwork coming down from the attic.

Most of it got sealed using just caulk but there were two ducts that needed spray foam for various reasons.

The smell was always tolerable but we're talking a very tiny amount compared to doing a whole house.

Greatstuff and the like is a one part foam however. Much less to go wrong since all of the chemistry is handled during production. Just make sure it is warm enough but not too hot, have some mineral spirits on hand for clean up and you should be good to go. The two part foams... Well a lot can go wrong with those... Up too and including catching the structure on fire during the curing process. It is an exothermic reaction.


https://www.greenbuildingadvisor.com/article/three-massachusetts-home-fires-linked-to-spray-foam-installation

Mad Dog_2

I'm sorry, I'm not putting ANYTHING that is/has been used to embalm human bodies (formaldehyde) in my family's living space. The other BIG problem is having to run or snake a wire or pipe through those walls and ceilings later on....nightmare on Elm Street!  That being said,  the Icynene type insulates super-well...like the interior of a thermos or cooler ..   Mad Dog

JakeCK

Formaldehyde is everywhere. It is naturally occurring as well. We actually have enzymes that can metabolize it, and in fact our own bodies produce it constantly. 

ChrisJ

Mad Dog_2 said:

I'm sorry, I'm not putting ANYTHING that is/has been used to embalm human bodies (formaldehyde) in my family's living space. The other BIG problem is having to run or snake a wire or pipe through those walls and ceilings later on....nightmare on Elm Street!  That being said,  the Icynene type insulates super-well...like the interior of a thermos or cooler ..   Mad Dog

You've been around formaldehyde a whole lot more than you think.  Every day.

Not to mention your body produces it.

MikeL_2

   I was never a fan of csst for gas piping. Especially after seeing it pierced by a small nail as it was held captive by spray foam in an exterior wall; an unsuspecting homeowner was trying to hang some artwork.
   I'm thankful for this thread because I wasn't aware that the modern generation of spray foam has hazardous qualities........

ChrisJ

MikeL_2 said:

   I was never a fan of csst for gas piping. Especially after seeing it pierced by a small nail as it was held captive by spray foam in an exterior wall; an unsuspecting homeowner was trying to hang some artwork.
   I'm thankful for this thread because I wasn't aware that the modern generation of spray foam has hazardous qualities........

I didn't see any conclusive evidence in this thread that modern spray foam is hazardous?
I see opinions and speculations.

That's about it. And I think they were even presented as such.
There's concerns about getting the mixture correct, but that could be said for a lot of things.

As far as I'm aware there's two part expanding foam you make by mixing two liquids.

However, I believe the stuff used in walls, attics, floors etc is done automatically by the sprayer and all you do is connect two tanks to it. I don't believe there's any control or changes that can be made so I have a feel there's no concern over mixture issues in this case.

But, again, even here this is speculation on my part.

This doesn't show any adjustments that can be made.
https://youtu.be/HMamnTBtusk

Jamie Hall

Oddly enough, the Wikipedia article https://en.wikipedia.org/wiki/Formaldehyde on formaldehyde is pretty good, if you want to read up on it. As several folks have stated, the problem with two part foams is in the mixing. The hope is that neither component, unreacted or partially reacted, is sufficiently hazardous as to make mixing really critical.

I personally have not had good experiences with urea-formaldehyde foams, due to continued out-gassing of partially reacted formaldehyde.

ethicalpaul

This guy is a foam contractor, so obviously keep that in mind, but his videos seem really good to me. Somewhere in his history he has a video where he talks about the issue of roof leaks, etc, but here's a general "things to watch out for" to get you started:

https://www.youtube.com/watch?v=zvL4va6P5F0

IIRC he's in Canada, so reasonably regulated, and he uses 2-part closed-cell foam.

reggi

STEAM DOCTOR said:

National Grid (gas supplier) is offering free foam insulation. 

Are they offering to install for FREE  also? 
I'd go for it..

Mad Dog_2

I'm sure its "everywhere" and naturally occurring, but like asbestos, oil burner soot and smog, I'm not going out of my way to breathe  formaldehyde...When's the last time you wiffed are jar of formaldehyde?   I was around it quite a bit around the family funeral home as a kid...its nauseating.  Mad Dog 

Larry Weingarten

Hi, I think this is experience based info. https://www.cbc.ca/news/spray-foam-insulation-can-make-some-homes-unlivable-1.2224287

Yours, Larry

Mad Dog_2

I've got enough "DRAIN-BAMAGE"  🥴 🙃 😅 from years of  PVC Glue and Testors Model plane  Glue!!  Don't wanna make it worse with Formaldehyde...ha ha.  Mad Dog 🐕 🤣 

MikeL_2

     Let me count the ways:
Indiscriminate asbestos removal from piping & ductwork.
Inhaling fumes during melting & pouring lead joints.
Soldering with lead bearing solder.
Exposure to lead paint, asbestos, & mercury during demolition. 
Raw sewage including toxins & parasites. 
Radon.
Confined spaces with poor air quality.
Work place excessive decibel levels.

Mad Dog_2

Exposed to everything you mentioned but very fortunately I entered in 1986 when asbestos awareness was just gaining traction..Lost 3 or 4 jobs over refusing to Remove improperly.  By 88 I was certified on abatement, so I knew EXACTLY the right way. I left the "Onion" (Union) for 5 yrs and was going to attend Law School over this!
The spray on stuff is supposedly flammable when spraying (comforting!).  After Hurricane Sandy I ran a Union  crew that got all the Public Schools on the Rockaway Peninsula (Queens)  back running . I got a call from the Big Boss on a Friday Night that a sump pump was OOS in a deep crawlspace under Beach Channel HS.  A Spray Crew was under there applying. They sent Mad Dog The Tunnel Rat 🐀 In....No respirator...STUPIDO-MENTE! It was about a 300 foot crawl on your hands and knees dragging a Sump pump. Visiblity was 50% even with floodlights..I got in about 50 feet, could not breathe and withdrew.  THAT stuff was nasty, I coughed for days and Lungs were definitely affected.  My Bad!  Even Osha-man (One of my co workers nicknames for me) tries to wing it for the cause...DUMB...who cares if the place floods again..Should have waited till I had the proper organic vapor Respirator before going in.. Wife, house,, 3.kids big tuition bills..you don't wanna lose your job over it,, but you can always get another job...not another set of lungs, eyes, et cetera. Pay attention Kids!  Not worth it. Mad Dog

TAG

Jamie Hall said:

Closed cell foam is a real problem with roof leaks, as it will trap the water. Open cell is much less of a problem -- but a big leak would still be a problem. If the roof is in good shape and kept that way, not to worry. Much...

IM O fiberglass is more of a problem because it hold water -- the foam seals the bottom of the framing ...

I'm a closed cell guy and I do like the stiff ... that said I always do proper roof work. Best not have any leaks with any system

The Steam Whisperer

Foam has some real advantages....It adds significantly to the lateral stability of the structure, does a great job of air sealing and has a high insulation value. However, looking at the long term, I don't think its a good idea. Jamie sees this, any kind of water leaks trap water in the framing and buildings will always have leaks at some point... buildings built even by the wealthy in all the best and most desirable places will eventually fall into disrepair for periods of time before the area is renewed by a future generation. Also what happens when building usage and needs change. Foamed walls are very difficult to remodel for new uses. I see foamed wood framed wall structures ending to become throw away buildings because of the great limitations to future redevelopment.

TAG said:

Jamie Hall said:

Closed cell foam is a real problem with roof leaks, as it will trap the water. Open cell is much less of a problem -- but a big leak would still be a problem. If the roof is in good shape and kept that way, not to worry. Much...

IM O fiberglass is more of a problem because it hold water -- the foam seals the bottom of the framing ...

I'm a closed cell guy and I do like the stiff ... that said I always do proper roof work. Best not have any leaks with any system

In this example, fiberglass can be removed and the damaged deck and framing repaired while preserving nearly all of the structure. Foam makes this much more difficult and costly, probably making it much more likely the structure will need to be razed due to economic limitations of the extra cost to repair. This seems to be very wasteful, which is at odds to why foam would be used in the first place. Fiberglass insulated walls with the simple well developed air tight drywall building techniques give exceptional performance thermal while keeping the structure quite repairable for the future.

Now, if you are looking at a curtainwall design using removable foam insulated panels hung on a structure, that a whole different animal that would make lots of sense.

ratio

The Steam Whisperer said:

I see foamed wood framed wall structures ending to become throw away buildings because of the great limitations to future redevelopment.

Not sure this will be counted in the minus column. Around here, they're starting to tear down buildings that I remember being built.

To be sure, gentrification is driving the bulldozer, but still…

PC7060

Open cell foam is easy to remove later if required. 

And as Jamie pointed out, it won’t trap moisture like closed cell. 

melvinmelvin

What climate zone are you in? That will determine whether you need closed cell foam. Closed cell functions as a vapor barrier. You need this if you are in climate zones 4 and 5 unless you are painting the bays first with vapor barrier paint, or drywalling over it, mudding and taping the seams, priming and painting it. Open cell without the above or duhumidifier or otherwise conditioning your attic will rot your roof deck starting with the ridge. The code is written to support this rhetoric.

Everyone on The Wall knows why. Warm air rises. It is more bouyant than cooler air. In the warm air are all the water molecules too. In climate zones 4 and 5, winter is colder than the others. The ridge will be colder for longer. The extended visit from the water vapor will end up rotting your ridge if they can get to it. That’s why roof venting still works under certain circumstances. You can probably use open cell in climate zones 4 and 5 if you were spraying the floor where the collar ties go instead of spraying the roof deck all the way up, but that isn’t code. Yet. It may become code at one point, but isn’t now.

The other statements about foam trapping water if there’s a roof leak/open cell is better. Those are parroting marketing statements THAT COME FROM THE OPEN CELL FOAM INDUSTRY.

Fix the leaks first. You don’t choose your insulation because it makes roof leaks manifest. You choose it for performance/inch by your budget.

If you were replacing shingles, pay attention to what Larry Weingarten stated above. If you install ridgid insulation ABOVE the roof deck and UNDER the shingles, you can do anything you want underneath.

ChrisJ

I personally feel a vapor barrier is just as important in a hot humid climate as it is where it's cold.

If you've got a dew point of 80-90F outside and you're running A/C in the low 70s you're going to have a problem without a decent vapor barrier. No?

STEAM DOCTOR

@melvinmelvin. I am speaking purely as a layman. Let's say I fix roof. Let's even say that I install a new roof. Then I spray foam. The turns out the roofing company messed up here or there. It happens. Or let's say there is a storm and some shingles blow off or out of place. Certainly happens (and like most people, I don't have the time or the ability to get up on my roof to do a proper inspection after every storm). What happens to the water that penetrates the roof? Does is sit on the wood and rot it away?

Jamie Hall

Despite @melvinmelvin 's enthusiastic sales pitch for closed cell foam, no one type of insulation is best in very application. Some applications are best served by one type, some by some other type -- and there are dozens of types and applications. It is well to not listen to a salesman, as they will only pitch their type, but try to find honest evaluations of the advantages -- and disadvantages -- of each type.

I might mention, although it's minor -- adding thickness to a roof by placing foam on top may not be as easy as it sounds, particularly if one wants any reasonable thickness. Another minor point -- affecting only a tiny fraction of people -- is that spray foam is not reversible (someone up there said it could be removed. Um... no...). This is only a consideration in certain historic renovation projects.

I response to @STEAM DOCTOR question just above -- the only time I have seen serious rot damage in a foam insulated roof or deck is when water actively got in from the outside through damage.

ChrisJ

I think the best part of this whole discussion is that some people actually believe a new roof would automatically be perfect and couldn't possibly have any leaks or failures.

Mad Dog_2

Ask my father in law...he just paid some "roofing experts" big bucks to fix his roof....At 78, he's fixing it himself..alot of shyster, Jack-Leg, Stumblebum roofers out there.  Mad Dog

ChrisJ

Mad Dog_2 said:

Ask my father in law...he just paid some "roofing experts" big bucks to fix his roof....At 78, he's fixing it himself..alot of shyster, Jack-Leg, Stumblebum roofers out there.  Mad Dog

You can take out "Roofers" and replace it with every trade.

PC7060

I personally will not foam directly to the roof sheathing. We create vent channels from soffit to ridge and foam to that. Roofs need to breathe.  

JakeCK

Jamie Hall said:

 Another minor point -- affecting only a tiny fraction of people -- is that spray foam is not reversible (someone up there said it could be removed. Um... no...). This is only a consideration in certain historic renovation projects.

Hey, it is removable... You just have to remove the framing with it. Lol

I also want to add that the difficulty in removing it is also why it increases the strength and rigidity of the structure. I've heard numbers such as 300% thrown out there. If you live in earthquake or hurricane country this could be a very big advantage to it. Hurricane ties and closed cell spray foam over top of the framing before the finish surfaces are up and you'll have the strongest house on the street. 

PC7060

Open cell is straightforward to remove from framing although it’s a mess to pickup and bag.  It does leave a residue.   But agree with Jamie, I used a different system for historic portions of my house where reversal is a requirement. I found BIBS to be good solution. 

melvinmelvin

Jamie Hall, I’m not a sales person and that wasn’t a sales pitch. I’m material agnostic. I never claimed that closed cell was good for every application. I’m merely answering the OP’s question: Should I take the utility up of free foam to spray in my roof? If you want to chat with me about the physics, let’s do it. 978-394-3285

melvinmelvin

@steam doctor, I was lucky enough to work for one of the foremost building science consultants out there for nearly a decade and a half. I was the only one there without a professional degree. I got the coffee and set up conferences and got to read a lot and sit in on formal and informal discussions and seminars. I got to be a part of research projects and tear apart roof assemblies And put them back together and got to gather data. And lots of non-glamorous work too. A lot. It was a blast. The standard answer for that question when we got it was “we have heard that claim for 30+ years and are waiting for out first one to investigate.” It’s not a thing. They would know. They would know. It’s simply a talking point from the other side. All manufacturers do this for all building products to some extent. They sometimes invent bogeyman that their product or association or federation, and theirs alone, can defeat. 

Sprayfoam isn’t straightforward and unlike anything else, should not be attempted without supervision. It is literally manufacturing- but the factory is the field. Lots of variables that need to be controlled for. But the trapped water and rotted roof from a pool of water from an undiscovered roof leak isn’t one of them.

Open cell works in climate zone 4 and 5 with the caveats I stated earlier. Closed cell works everywhere.