spray on insulation?

[Melissa]

We will be removing all the drywall on the west side of our central FL home shortly, it all needs replacing due to termite and hurricane damage. I recently saw a home improvement show that demonstrated a spray on insulation. It was made of soy, and it expanded after being sprayed on the inside of the outer wall. It was then cut flush with the studs before the drywall was put in place. Our west side gets full sun, and the rooms get measurably warmer. This is one of the long sides of our rectangular shaped home. We've just replaced doors and windows, but even in early June you can feel the difference from the east to west side of the home. We currently have fiberglass batting, but it's been damaged by water in most of the west walls. Any opinions on whether this be a product worth looking into, and if so, who would you contact to do this sort of work or can it be done DIY? Any ideas on how it compares costwise to fiberglass batting replacement?

Melissa

[tbasc]

Research the material carefully. Look for installations that have been in place for a long time. I've seen a number of spray in or foam in products come and go. Since it is soy based, how does it hold up with termites and rodents? I would guess that special equipment is needed and so it's not a DIY project. TB

[Edwin Pawlowski]

It has been around a few years. It is an polyurethane but with a soy oil base. Soy is being used in many areas where other oils used to reign, such as stains and top coats. I don't think it would be a rodent problems any more than similar material with other bases. In the conversion process it is no longer a food but more like a petro-chemical

[Edwin Pawlowski]

Start here

[tbasc]

Edwin, Thanks for the links. I'm not surprised that there is a switch to organics from petro chemicals, but I wasn't aware of the changes you note. TB

[Slumlord]

stabalized cellulose maybe what you are looking for. Its a recycled paper treated with boric acid (making it fire, mold, and pest resistant). The stabalized part is an addition of starch, which makes it sticky when spay through a water mist. It works waaay better than fiberglass. You can also install it by putting a nylon netting across the studs and dry blowing it in (I normally do this). The overall effect is the same.

Melissa wrote:

[Philip Lewis]

That would be the immediately economical choice. Cellulose seems to be the most insulative per inch, and doesn't suffer from extreme temperature R value losses like fiberglass does. The glue matrix in the wet pack cellulose keeps it from settling, the most cited disadvantage of cellulose.

Another more expensive choice would be the spray on foam. about twice the R per inch of most anything else, good air infiltration protection (cellulose provides some as well). It might even add some structural integrety... there are engineered panels that are essentially plywood sheets on either side of a foam core. Could be good in hurricane territory.

The only place I've seen a DIY source for foam is at

... I've been considering them for my retrofit insulation job. (old victorian, probably balloon framing... no insulation) They have a slow cure version that will allow for retrofit.

Anyone know of any others? Always looking for options.

[Slumlord]

I use Fomo's products. Very good! But not cheap.. I use foam for air-sealing and sealing places that I can't use cellulose (wet basement walls, cripple plates where nothing is available to hold the cellulose in place, etc.) A word of caution using foam on frame buildings. If you get moisure (which WILL happen in places with high humidity and hurricanes) under the siding, the sheeting can dry out if you have cellulose. Water vapor will pass through the sheeting, cellulose, and the sheetrock. Foam is vapor tight. The sheeting will stay wet, possible causing a rot problem.

Philip Lewis wrote:

[Goedjn]

Fill your walls with cockroach food?

[Wayne Whitney]

I was under the impression that spray-foam insulations came in two varieties, open cell and closed cell, and that while closed cell insulation is vapor tight, open cell is not. So wouldn't open cell foam work in this situation?

Cheers, Wayne

[Edwin Pawlowski]

Not at all. Learn about it and you will see.