denim insulation?

Unfortunately, I found out about this Airkrete, after my insulation was complete. It is hard to stay ahead of all the information needed to make good choices, as there are so any choices. If I had to do it over, I'd use it.

http://www.airkrete.com/

https://m.youtube.com/watch?v=ll7BlFwNxPI

Here is a link that might be useful: planet green video on Airkrete

Thanks! Right after I posted this I found AirKrete too! It looks like a great product and I'm hoping we can afford it!

Please keep us updated.

"For cavity insulation, I might argue that cellulose or fiberglass has just as many concerns as spray foam. At least spray foam will better stop air movement which helps reduce humid air flowing through building cavities which increases risks of hidden mold. "

I'd add that the same holds true for wall & attic insulation.
if the wall is air tight to start with,
(housewrap installed properly etc and air tight drywall approach
to interior) then there is no air moving through the wall cavity
to introduce into the living space any insulation particles.

by the same token if you put insulation on attic floor..and
ceiling of living space is full of unsealed holes ( IC recessed
lights, oversized cuts for hvac supply boxes & bath fans
just to name a few holes...then attic air will enter the
living space when central system comes on. with this
extreme temp attic air, as it filters through the insulation
it brings in particles of insulation & dust.

properly installed spray foam seals air leakage & insulates
in one...but at a hefty price.

the term 'toxic insulation' is offensive in that no insulation
is good for you...but we aren't eating the stuff.
put insulation in a sealed wall or ceiling & there is no
toxicity entering the living space.

air seal and what you put in walls & attic isn't an issue.

best of luck.

I'm worried about the off gassing of foam...I guess I'll look into icynene since I can't seem to find a Air Krete contractor around here...

@ LMRinc - I used this form on their website to names of local vendors. They responded quickly.

I'm worried about the off gassing of foam

Most "indoor air pollution" comes from decor and human activities, not the insulation.

A good air exchanger to introduce outside air and distribute it will solve the problem.

Thanks for the short version lazygardens. An air exchanger providing outdoor air is a balanced ventilation approach and preferred by most experts. This is also known as an HRV or ERV. All they are is a fan with a heat exchanger.

Icynene, implies that you are only concerned with cavity insulation (insulation between framing) which usually means that 25% of the building envelope has severe thermal bridging and related energy loss. Again, foam in the form of "insulative sheathing" is much more powerful and where the building codes are headed.

What you should be worried about is humid air flowing through your building cavities and thats something Aircrete is likely to contribute to without the proper air-barriers to prevent it.

roxul

We are also looking for insulation that is allergy friendly and mold resistant. I've been reading up on roxul and it looks good. Is there a down side?

Btw we are in toronto - so it gets cold some of the time.

Roxul is North America's leading brand of Mineral Wool, which is probably the fastest growing insulation type other than spray foam. It has some appealing properties, namely moisture and fire resistance.

The biggest problem with focusing on this product as an alternative is that its still mainly a cavity insulation. It can still suffer the same serious downsides of batt installation, but it does seem to offer advantages in this area as it holds its shape better than other batts (fiberglass, denim) which makes it easier to avoid the usual problems of not filling the entire cavity which is a very tough thing to do for batt installation in framing cavities.

Ive read that people are using it for blown loose fill in attics. All attic loose fill details being equal, this seems like a good fit but wonder if its worth any price increase. As to prices, this is highly variable and the last time I priced it in our area it was roughly 2x as much as fiberglass batts which approaches dense pack and spray foam.

Roxul mineral wool is apparently still using formaldehyde as a binder which baffles me. All manufacturers are getting away from using this chemical and its probably only a matter of time before Roxul makes its acrylic binder product available in North America. Until this issue is addressed, its possible that spray foam will have less measurable negative IAQ consequences than mineral wool.

Again (as many times as it takes), outdoor air introduction is more important than building material selection. If you arent providing a means of outdoor air ventilation, then youre wasting your resources with these toxicity reducing exercises.

Some builders have taken to using mineral wool panels as exterior insulative sheathing, which is probably the biggest improvement one can make to traditional wood framing and best insulation practices. Air-sealing being equal of course!

Here is a link that might be useful: GBA article on using Mineral Wool as insulative sheathing

rock wool...good stuff. but you won't get the
air sealing you will with foam.
and given a choice, I'd pick foam sheathing
to exterior rather than the product
in the excellent GBA article.
(thanks for the link Brian).

I'm a big advocate of building tight, and ventilating
right. it just makes too much sense.
I've seen houses built to 'breathe'
and with controlled ventilation.
on the former the builder/hvac or insulator
talked homeowner into not air sealing,
the latter homes were sealed.
funny...I get both clients, the ones who
can't afford the utility bills & health issues,
and the ones who followed the house as
a system when building.

it is always easier to build things right than
to go back & make things right.
now is the easiest time ever in the future of your
home to assure comfort & affordability.
and a healthy home.

I have to say...being in a hot humid climate that
the old & the modified ventilation standards leave
us out of the equation. whole house dehumidifiers
with fresh air intakes are our best method of adding
fresh air into tight homes.

best of luck OP, and keep researching.

Thanks everyone....I'm excited about every detail of the house and I want to get it right! I am allergic to formaldehyde so I need to avoid it in the product and if roxsul uses it that's a no go. I know if will be behind walls but if it degrades at all and gets in the air I'm in trouble.

I'm thinking of icynene on the roof and if I can find a great hemp batt or no formaldehyde insulation...I'd like to know if that sounds smart?

I would love to do airkrete but no one will get back with me...

Hello forum,

We are building a new house in NY and are completely undecisive about insulation.
The walls are 2x6 and the roof is 2x12. Outside is 3/4" plywood, then brick/stucco.
Contractor suggested using 2" Dow Super TUFF-R insulation boards (R 13). He will cut them, place them between the studs in the middle of 6" space creating an air space (this should add R 2.8) and spray foam around the edges. Since he'll do it himself the cost is less than any other alternative. The question is - is this the right insulation from the point of "house should be breathing", etc?

The alternative is Owens Corning R-21/R 38 EcoTouch® PINK® Fiberglass.

Thank you for your help
Lenny

Here is a link that might be useful: DOW TUFF-R

I bought a few truckloads of salvaged commercial 4 and 5-inch thick rigid polyISO sheets that are unfaced. I cut them to fit the wall cavities and then sealed all seams with bullet cans of fire block foam. Some of the rooms and the attic have been insulated for three years now and there has been absolutely no sense of outgassing, and my wife is very sensitive and I can't even walk through a department store perfume section without my eyes watering.

In fact, the green flooring we are putting down is far worse. It starts off smelling like cut grass and then for about three months after it smells like urine when you first walk in the room. After three months, the rooms finally smell fresh again.

I can't speak to the spray-in polyISO, but the manufactured sheets seem to be pretty safe to use. I would certainly use it again, although the sheet polyISO is terribly labor intensive to install. It's a lot of meticulous work. Great insulation, however. It's been well worth the effort.

"We are also looking for insulation that is allergy friendly and mold resistant."

So were we. We have already had issues with carpet/paint smell and other chemical triggers. It took us over 6 months to move into our house because of it. We plan to use organic wool instead. It doesn't off gas, is fireproof and doesn't require the installer to wear protective gear.

"Tracy Nelson summed up the dilemma this way: "Here is the simple truth of spray foam in an existing building: Mixing this material in the field can be inconsistent and as mentioned many times above, completely depends on the skill level of the installer (don't confuse the actual person who shows up at the property with the company who sells you the product and promotes themselves as experts)."

"William Swietlik, who identified himself as a member of the Federal Interagency Spray Polyurethane Foam Worksgroup and co-chair of the EPA's workgroup on spray foam, said that both open- and closed-cell foams are made with diisocyanates, among other ingredients, a leading cause of workplace asthma and a "well-known sensitizing toxicant to humans." He added: "Once an individual becomes sensitized to diisocyanates there may be no safe exposure level."

Links that might be useful.

http://www.greenbuildingadvisor.com/blogs/dept/qa-spotlight/does-spray-foam-insulation-gas-poisonous-fumes

http://www.oregonshepherd.com/

Lenny, that is not the way Insulation boards are typically installed and there are not many that would recommend doing it that way (using it as cavity insulation).

Usually insulation board stock is used as an "insulative sheathing". Its meant to wrap the entire wall, studs and structural sheathing (OSB, Plywood). Not only does this reduce the thermal bridging of all the 2x studs and framing, it keeps the structural sheathing warmer and above the dew point which reduces condensation risk.

Using it in the way you describe could perform worse than fiberglass batts as it would be difficult to fill the entire cavity and I can almost guarantee the sprayfoam in the gaps would not hold up well to typical building movements throughout time. 2" foam board is great, but use it as insulative sheathing NOT cavity insulation.

rmtdoug, I agree. Iam very sensitive to chemical smells, and in my experience, finish flooring (and subflooring) is much worse than spray foam.

Dreamgarden and others concerned with spray foam, you have every right to be concerned with this product. That is a good link and in the author's concluding paragrapgh quote: " ..it is easy to see they are [problems] all for the most part human error" meaning, its installation errors that lead to problems.

Spray foam is not the only option for energy efficient homes and PLEASE be aware that sprayfoam as cavity insulation is MUCH different than foam as insulative sheathing both in terms of energy performance and IAQ risks. Most importantly, if you are not addressing ASHRAE 62.2 or providing outdoor air with a ventilation system, spray foam as cavity insulation should be the least of your concerns until you do.

This post was edited by Brian_Knight on Mon, Oct 20, 14 at 20:17

Brian,

Thank you very much for your reply.

Is it OK to go with the Pink insulation for the cavity and ask contractor to put the TUFF-R on the outside - between plywood and the brick/stucco. Is 0.5" sufficient?

Look into Spider Insulation System.
It is mold resistant and R-23 if you use 2x6.
I used this in one of the houses I built and I'd use it again.
I also used Icynene in the past with no problems.
See link.

Here is a link that might be useful: Spider

Your welcome Lenny and thanks for thinking that Iam a guy on the internet worth asking.. This gets a little opiniony knowing squat about your situation involving many variables but.. probably not, yes and no in the same order you asked.

I have no idea what level of code is enforced in your area but I highly suggest sticking to the minimum levels of energy performance called for in the International codes. IECC 2012 is about to have its 2015 update and Iam excited to find out how wrong or right I am in squawking how they arent going to raise many insulation requirements but blower door testing will see a lot of very overdue attention.

This thread is long overdue, for a serious plug on reducing uncontrolled air leakage. If your home is not a certain level of airtightness, then insulation can be an enormous waste of resources. If you are concerned about reducing your exposure to toxic air then focusing on the interior materials is a waste, if youre not building tight and ventilating it right with the "home as a system" priority.

Insulation is expensive compared to airsealing and less effective in terms of overall energy performance. Uncontrolled, moving air carries a lot of moisture that does serious damage when moving through building cavities and thermal enclosures. It also leads to condensation and mold, especially in poorly installed fiberglass batt wood framed wall cavities with small levels of insulative sheathing. Add in a good vapor source, moisture reservoir cladding like stucco and brick that really soaks in the rain and drives it to the interior when the sun comes up and you contribute to much job security for those in renovation. But hey, it could be fine if the masonry has a good draining and ventilating airspace and that 1/2 piece of foam is well taped foil face isocyanurate, and the wall cavities are air sealed on all six sides with a dense batt filling all voids.

I suggest pricing between OC spray foam and dense pack cellulose or FG (not batt). These are the things that best achieve a completely filled wood frame cavity. If not venting the roof deck, I suggest spray foam or insulative sheathing to the exterior.

More important than insulation, is your ACH50 as measured by a blower door. The level of air leakiness in most homes is unacceptable leading to massive amounts of energy loss and unhealthy indoor air conditions. The code calls for an ACH50 of 3 or lower for building climate zones 5 and 6. I think that's pathetically leaky and not at all appropriate for a home built with the current international levels of insulation in the code. Homes in all climate zones should be pushing hard for an ACH 50 of 1.5 or less. Cost effective energy efficiency, increased durability and moisture resistance, and the ability to control the cfm rate of outdoor air exchange, which is probably the best way of improving Indoor Air Quality.

As for levels of insulative sheathing, cant explain it any better than Martin at GBA. Its an important detail for everything weveve talked about, cost-effective energy efficiency, increasing indoor air quality and durability of the building envelope. Minimum For 2x6 in zone 5: R7.5 and zone 6: R11.25.

Even 1" Isocyanurate with a foil facing the air cavity will be slightly below code and risky as far as interior condensation. I would do my best to get 2" thickness, even if it meant falling back to 2x4 instead of 2x6. I also suggest everyone to set a goal for ACH50, inform your builder that you expect to meet it and hire a third party to do a blower door test which puts a number on the value of the integrity of your home in terms of energy efficiency, indoor air quality and healthier building science.

Here is a link that might be useful: Calculating the minimum thickness of insulative sheathing

Nafs link is a form of dense pack fiberglass (not batts). You can use cellulose the same way with slightly lower R values. Its still mainly a cavity insulation but can also be used as loose fill in vented attics. In my experience OC spray foam is very cost competitive with dense pack and is reputed to block air movement better which isnt as much of a concern above the airsealed floor of a vented attic. Both FG and cellulose have indoor air concerns but cellulose is usually seen as the more sustainable choice. I would argue FG (densepack) has better air quality than cellulose but that's mostly irrelevant if youve been paying attention.

Most climates with heating needs should still consider insulative sheathing or might be required to by local or international codes depending how cold they get.

Brian - Excellent information. Your point on stopping all air infiltration is spot on. I believe it is the single most important aspect of building or remodeling a house.

I started to figure all this out about three years ago when I embarked on my remodel. Unfortunately, cavity insulation was all I could do, so I concentrated on making sure the house would be well insulated and airtight but still able to breathe, which is important in my temperate marine climate.

Brian - great and useful stuff. Appreciate your advice.