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-   -   Who knows anything about closed cell spray foam house insulation? (http://www.bikeforums.net/foo/449849-who-knows-anything-about-closed-cell-spray-foam-house-insulation.html)

patentcad 08-04-08 07:45 AM

Who knows anything about closed cell spray foam house insulation?
 
Any known toxic issues? Also, they want to eliminate the attic venting. They say that's fine. I'm skeptical.

jsharr 08-04-08 07:53 AM

Not sure about insulation uses, but I work for a company that pours closed cell polyurethane foam. Once it is reacted, there is not a hazard. We make foam footballs for kids to play with. Hard to make the stuff burn. We pass every QC test we take, even with all the big retailers. My kids use our products all the time. Hope this helps.

BTW, we use water as a blowing agent for our foam, I have heard that other foams use other blowing agents, and some of those are not good.

patentcad 08-04-08 07:59 AM

So you're saying we should spray foam all the young kids here in the neighborhood? That might quiet things down a bit.

jsharr 08-04-08 08:02 AM

Sounds good to me. Really, you should put the kids in molds, and then pour the foam around them. Gives you more possibilities to create interesting shapes, but your upfront tooling costs are really gonna be higher with my plan.

rm -rf 08-04-08 08:28 AM

Eliminating attic ventilation doesn't sound good at all. Is this just some of the vents?

patentcad 08-04-08 08:37 AM

Quote:

Originally Posted by rm -rf (Post 7200895)
Eliminating attic ventilation doesn't sound good at all. Is this just some of the vents?

I have to agree. It's one of my reservations about doing this. The companies claim that it's OK because condensation can't form on the closed cell foam which is on the underside of the roof planking. Still doing research.

ilikebikes 08-04-08 10:23 AM

I dont know if its the same stuff or not as its on a much smaller scale but here it goes. I use Great Stuff! Foam for the backgrounds on my terrariums and have never had a problem. 90% of the time I keep frogs in the set ups, they are VERY sensative to toxins and chemicals and have gone on to live their little lives and even breed! Ive gone as far as using it in aquarium set ups with zero fatalities! :) (all this is after the poduct has fully cured )

trsidn 08-04-08 10:26 AM

Quote:

Originally Posted by patentcad (Post 7200614)
Any known toxic issues? Also, they want to eliminate the attic venting. They say that's fine. I'm skeptical.

Gotta look into this, but on the face of it, seems like a bad idea.

After the foam insulation cures, I am pretty sure there is no toxicity issue
.

Alfster 08-04-08 10:46 AM

Here's an excerpt from a "Technical Consultant to the Sprayed Polyurethane Foam Industry" report. I believe it refers to the Ontario Building Code:

"stating that “where a roof assembly is filled with rigid insulation (no gaps or empty
space in between), Subsection 9.19 of the OBC need not apply and may be considered to be
acceptable under sufficiency of compliance in Section 2.7 of the OBC. This opinion is based on the
fact that, if a roof assembly does not contain any air space or air pockets in between, air will not
turn into vapour and condense within such an assembly even under extreme weather condition.”
The requirements are easing up and the above branch opinion of the Ministry of Housing clearly
recognizes this. However their opinion is based upon “filling the roof cavity” and they go on to state
why they want it filled. So really the issue is not whether sprayed polyurethane foam (SPF) can be
used at this location in the roof/ceiling assembly, but how.
Certainly the proposed assembly (SPF installed to the underside of the roof sheathing) with an airtight
low vapour permeance layer of sprayed polyurethane foam insulation eliminating any air
leakage to the roof underside meets the criteria of preventing condensation at the roof sheathing. If
it can be shown that leaving an air space between the SPF and the interior finish will not result in
any condensation within this air space, then the requirement for filling the space can be relaxed as
well. This determination can be achieved with a dewpoint/condensation potential analysis using the
data from the specific roof assembly as inputs. The following analysis represents a generic
cathedral ceiling and is equally applicable to flat roof assemblies."

http://www.cisudbury.ca/feedstream/c...tcathedral.pdf

hos13 08-04-08 10:52 AM

With out attic venting you may get excess ice build up on your roof.

SpongeDad 08-04-08 11:05 AM

It was very popular where I grew up, but I believe there were concerns later on that the house were sealed up too well. Without some airflow house get stuffy and becomes incubator like.

Michigander 08-04-08 11:13 AM

Keep the venting! I've had to do an awful lot of roof jobs that were premature, and simply caused by a lack of ventilation. The more vents the better!

As for the insulation, I would just use the news paper based stuff that somehow manages to be incredibly fire resistant. That or maybe some good old fashion fiber glass wool. Cheaper, and probably works about as well if done right. The one and only thing I would ever, and as a matter of fact have ever used spray foam for is getting into small spaces. The stuff is just plain too expensive to use massive amounts.

USAZorro 08-04-08 11:17 AM

Quote:

Originally Posted by patentcad (Post 7200958)
I have to agree. It's one of my reservations about doing this. The companies claim that it's OK because condensation can't form on the closed cell foam which is on the underside of the roof planking. Still doing research.

I believe that monolithic domes utilize closed cell insulation, and are often unvented.

spoketacular 08-04-08 12:08 PM

My Quasi-GF's house has the foam stuff in the walls, but interestingly enough, they didn't insulate the attic that much (very common here in California). When she had the contractors upgrade what little was in the attic, it made a HUGE difference in how steady the temps stay in the house now. We can get away with the a/c hardly running at all unless the temperature has been pushing 100 here in Sacramento for a few days and hasn't cooled down much at night. Probably only runs an hour a day, because once the sun goes down, and the Delta breeze kicks in, we can pull in enough cool air the whole house fan the house is in the mid 60s by morning.

Anyway, when contractors say its a waste of money to do the walls - that the attic is most critical - they appear to be telling the truth from my limited experience.

patentcad 08-04-08 12:16 PM

We are talking to a contractor about doing the attic only.

mlts22 08-04-08 12:24 PM

I just like stuff like cellulose insulation, over foam. Its not whiz-bang, but it does the job, and you can still have your attic vents.

spoketacular 08-04-08 12:50 PM

Quote:

Originally Posted by patentcad (Post 7202604)
We are talking to a contractor about doing the attic only.

That's what I'd do. See how your heating/cooling bill works out over the next year. Simply sealing up your house, having good windows and attic insulation makes a huge difference. Awnings help in sunny climates, too, particularly in summer. In a four-season climate, though, you want that sunlight during the winter to help heat the house.

patentcad 08-04-08 12:55 PM

I am primarily concerned about sealing off the attic without venting, and the potential for dry-rot issues. Again, the closed cell foam industry say this isn't an issue. I have a white paper here from them underscoring their belief and presenting their case.

I remain unconvinced.

spoketacular 08-04-08 01:00 PM

Quote:

Originally Posted by patentcad (Post 7202896)
I am primarily concerned about sealing off the attic without venting, and the potential for dry-rot issues. Again, the closed cell foam industry say this isn't an issue. I have a white paper here from them underscoring their belief and presenting their case.

I remain unconvinced.

I think I'd just go conventional. That's what my GF did and she's very happy with the results. Its really the law of diminishing returns with tech innovation in insulation - spending more $$$ for an 'innovative tech' doesn't really figure out in the long-run cost/benefit ratios.

crash66 08-04-08 01:21 PM

Quote:

Originally Posted by jsharr (Post 7200676)
Not sure about insulation uses, but I work for a company that pours closed cell polyurethane foam. Once it is reacted, there is not a hazard. We make foam footballs for kids to play with. Hard to make the stuff burn. We pass every QC test we take, even with all the big retailers. My kids use our products all the time. Hope this helps.

BTW, we use water as a blowing agent for our foam, I have heard that other foams use other blowing agents, and some of those are not good.


Do not taunt Happy Fun Ball.

http://www.youtube.com/watch?v=weNH-rp1bWs

rm -rf 08-04-08 02:11 PM

I did a quick google on "closed cell house insulation" and all the links seem to be from the industry. It looks like it "could" work, since it's sprayed into the rafter bays, and covers the rafters, too. But any leakage of air could cause hidden water damage as the water vapor condenses against the roof. Is there any chance of shrinkage that would open up cracks? I also wonder if the shingle life would be affected by holding the summer heat in, right under the shingles.

Other new technologies have caused problems in the past. For instance, using staples on shingles and on roof sheathing made them less wind resistant. Plastic hot water pipe looked like a good idea until it started leaking after aging a few years. Older aluminum wiring needs retrofitting of copper pigtails in each outlet box.

Michigander 08-04-08 02:45 PM

What I have done in multiple instances in the past, is blow insulation into the walls, either by drilling a hole through the outside, after prying the siding back, or drilling through the drywall/plaster. (of course it's easier when the dry wall has been taken down or not installed yet and you can just blow it right in between the studs then cover it with the drywall) Then, blow a ton of it into the attic. In one case we used so much that the attic wasn't really useful for storage anymore. Then, we installed a bunch of soffit vents. It's always seemed to work. Only takes 2 or 3 days do a whole house, depending on man power with about 3 being optimal, and not counting the painting that may or may not have to be done subsequently.

It's stupifyingly easy. If you have the time, I'd suggest doing this stuff yourself, unless you really don't feel like it or don't have time. If you can tune a mountain bike's V brakes, you are ahead of the game for skill level with insulating a home.

patentcad 08-04-08 03:12 PM

Quote:

Originally Posted by Michigander (Post 7203728)
What I have done in multiple instances in the past, is blow insulation into the walls, either by drilling a hole through the outside, after prying the siding back, or drilling through the drywall/plaster. (of course it's easier when the dry wall has been taken down or not installed yet and you can just blow it right in between the studs then cover it with the drywall) Then, blow a ton of it into the attic. In one case we used so much that the attic wasn't really useful for storage anymore. Then, we installed a bunch of soffit vents. It's always seemed to work. Only takes 2 or 3 days do a whole house, depending on man power with about 3 being optimal, and not counting the painting that may or may not have to be done subsequently.

It's stupifyingly easy. If you have the time, I'd suggest doing this stuff yourself, unless you really don't feel like it or don't have time. If you can tune a mountain bike's V brakes, you are ahead of the game for skill level with insulating a home.

The house already has soffit vents. These guys want to close them up. I remain, unconvinced.

'Easy work'? Dude, the extent of my home remodeling skills is changing light bulbs. IF I can find a chair that gives me the height I need.

mrbubbles 08-04-08 03:17 PM

Quote:

Originally Posted by patentcad (Post 7203893)
Dude, the extent of my home remodeling skills is changing light bulbs.

Be a man and grow some balls. You are AN AMERICAN HOMEOWNER. Learn to work the tools.

Alfster 08-04-08 03:27 PM

OK, if this site doesn't give you your answer, nothing will. It addresses vented, un-vented, and ice damming for both conditions.

http://www.buildingscience.com/docum...on?full_view=1


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