Closed cell foam Insul. VS Bat Insul.?

New Construction ready for insulation.
Should I use the foam for the CMU basement walls
that are studded.?
Sincerely,
Small contractor
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Replies
It is my thought that I would use a spray on foam over the CMU between the studs, but then I have become hung up on spray foam. Another thought is Astro-Foil. Check it out a http://www.insul.net
For regular insulation jobs, KEEP AWAY FROM THE BUBBLEPAK FOILS!!!!! It's all "smoke and mirrors". Gov'ts in US and Canada have done tests and R value disappears on site. They talk about radiant heat loss which is not the way most heat leaves buildings!!!
Depends which bubble pack you are speaking of. Reflectix, the stuff sold in box stores, is not tested. Astro-Foil is tested using ASTM C-236 for R value, ASTM E-84 for flame spread, etc. Hydro Canada approves it and offers rebates on Astro-Foil installations.
There is no gov't agency such as Hydro Canada.
The ASTM test does not breakdown the 4.8 value achieved by the "wall system" In still conditions such as the guareded hot box The air "stuck" on the drywall has an R value of .68. This will also apply to the air stuck on the outer foil surface facing the strapped cavity. so 4.8 minus 1.36= 3.44. At this R value, you might as well buy 1 inch of fiberglass batt (R 3.5) or foam board at about 1/3 to 1/5 the cost!!!!
There is no diagram to indicate where they installed the thermocouples......are they in the 3/4 inch cavity or are they on the outside of the plywood? makes a big difference if its outside the wood.
Used to be gov't energy analyst and regulator (among other building related jobs)...... have a list of 85 popular energy misconceptions which I call my "smoke and mirrors" list since most claims/statements contain a bit of truth but some of the embellishments step over the line to just about fraud". List goes from blown insulations to HRV's to foil insulations to ICF's and on. It is a fairly technical field and to understand it well, you have to have been close to it for a few years. I've been at it since 1977!!
I would be interested in your insight.. .e.g. fiberglass works fine, unless due to a leak it gets wet. I would like to give you a couple of applications and see what your insight is
But if due to a leak it gets wet, how much of it is wet? the whole attic or an area 1-2 inches in diameter. If it gets wet once, from this leak, it may cause a stain on the drywall and then dry out over a few days/weeks....no longterm damage that a paint brush won't correct.
I here these stories about whole attics with fiberglass soaked all the way through yet no one I talk to have first hand knowledge or pictures or research except for the very far north (and that's a whole other story where you can't vent attics, steel doors warped so much they developed a new weatherstripping for them, etc).
I've worked in and around the retrofit insulation industry for 29 years. The worst case I've seen was in New Brunswick (8500 deg days; fairly cold). In a very cold winter, the cellulose attic insulation was damp in the top 1 inch or so of 11". This house had very wet basement and damp interior, had no interior house venting and a loose ceiling so that a lot of warm, moist air escaped to the attic.......all a very bad situation you don't see in very many houses. I told the owner to start with cleaning up the inteior moisture problems- dry up the basement, vent the drier, bathroom and kitchen, air seal at the ceiling level. Don't touch the insulation; it will dry during the summer. The insulation dried and next winter only a little frost appeared in the attic leading to no problems.
Being from Florida, you should check out the Florida Solar Energy Center site for a research project they did to retrofit a house there with a variety of energy saving measures including new pool pump, additional attic venting, new A/C compressor, radiant barrier in the attic, new fridge (i think), etc, etc. The results for the attic venting and foil barrier are quite instructive of the over embellishments of industry. The payback in reduced A/C cost from the venting was 103 years!!!!!!! And the foil about 30 years!!!! Leave your money in the bank, these days it will make more than 3% a year again!
Pardon me, it was Onterio Hydro that offered the rebates.
Interesting thing happened on my way to an inpsection yesterday. Got a call from my old gov't dep't. They asked if I would be interested in attending a meeting/presentation by who of all possiblities.....the distributor of a super, fantastic, unbelieveable foil faced insulation who claims their expanded foam plus foil "TESTED" r values are:
3/8" = R14
1" = R28
2" = 48
ALL BS!!!!!!!!
Man! All the spray foam dealers better sell their equipment because they can't beat this one, no matter how much they embellish their claims!!!
Here's the website:
http://www.p2insulation.com/index.asp?id=12
Really looking forward to the meeting!!! Have got more than enough info/research to sink him!!!
Experienced,
Please do us a favor and tell us what you found during the presentation and your opinion after listening to the presentation.
Thanks,
Virginbuild
Yeah! I'll do that. We'll have to keep bumping this thread each week as the meeting is late May or early June- no set date yet.
Thanks! Knowledge is power.
Virginbuild
I was checking the Classifieds of a new small weekly paper for my area and found this ad for super, fantastic, unbelieveable insulation:
SAVE on HEATING COSTS- P2000, NEW high-performance Insulation, R27 performance one inch sheets- Versatile- quick, easy installation- tested, approved amazing!!
I dealt with a round of bubblepack foil covered insulation promotion from 1997-2000. The material now has pretty well no general usage in building here but is still sold in small quantities from hardware stores for wrapping pipes, etc. During that period, every time I saw a claim of high R, it was higher than the last one. The last one I saw was R16!! The stuff got better as time went on. I thought "Jeez, if I bought some now for my retirement house, it might be R 70-80 by the time I was ready to use it!! Great stuff!!" From the above ad, seems my thinking was right- foil + 1" expanded polystyrene is now R27 and 2" (from their manual) is R48.
The worst thing about the bubble wrap is that my daughter jumps on it and pops the bubbles before I can install it. What's the R-value of popped bubble wrap? <just kidding!>
My nephew installs foam insulation and mentioned to me one day that there is a huge difference between open cell and closed cell foam. The open cell foam can take on moisture and rot a building, whereas the closed cell will not.
My nephew installs foam insulation and mentioned to me one day that there is a huge difference between open cell and closed cell foam. The open cell foam can take on moisture and rot a building, whereas the closed cell will not.
OTOH some building scientists recommend open cell for roof decks because it allows drying to the inside.
What I wouldn't give to be able to see the code 50 years from now....
"OTOH some building scientists recommend open cell for roof decks because it allows drying to the inside."I would think that if there is that much moisture you would have a serious problem.
If you have moisture from a leak every rain, then drying to the inside will not make much of a difference since drying by diffusion is a very slow process. The wood members will rot before they dry.
If the moisture is from diffusion through the whole winter and theoretically less than a rain leak, the diffusion drying still may not be enough. During the winter as the moisture built up at the outer reaches of the foam (at the relatively vapour impervious panel sheathing), no rot will happen as this is cold/frozen (for us northerners) and mould won't grow (Note: all rot is by mould). In the early spring/summer, these outer temps are just perfect for mould and the sheathing hasn't dried yet......we begin to rot!!!
The front page of June/05 Energy Design Update (1 of my top reads) has an article about major rot failure in the walls and roof of a small house in Vermont (9000 Deg days) within 3 years of building. Icynene was installed with no vapour barrier over it. The place had only a cheap occupant controlled bathroom fan which led to high RH's. Apparently, Icynene recommends a VB in areas 7500 DD and up.
Edited 5/6/2006 10:27 am ET by experienced