Sources for DIY Spray Foam Insulation

[Wayne Whitney]

Hello,

I want to insulate 65 ft^2 of 2x4 wall with spray foam insulation, so I need 200 board-feet (ft^2-in) of insulation. I can have icynene sprayed professionally for about $0.65/board foot, but the minimum charge is $2500! So I'm looking for a DIY option.

I've found basically two options:

1) Handifoam kits (or equivalent), available online from fomofoam.com, tigerfoam.com, foampower.com, and betterfoam.com. This is a two part foam with an R-value/inch of 6.2-7.4 and a density of 1.75 lbs/ft^3. It is available in 22, 105, 205, and 605 board foot sizes.

2) Todol Purfill foam, available online from energyfederation.org. This is a onepart foam rated at an R-value/inch of 6.0 and a density of 1.2 lbs/ft^3. It is marketed for gap filling and comes in 20 board-foot canisters.

So, can anyone suggest any additional options?

The Todol Purfill foam is about 30%-50% less expensive than the Handifoam kits, and the R-value is comparable even though the density is 30% less. Would it be feasible to use the Todol gun for filling wall cavities, or will it just be too slow? How do one-part foams compare in general to two-part foams?

Thanks, Wayne

[Edwin Pawlowski]

No experience with this particular products so I can't comment on particulars. There is an optimal density for any foamed insulating material. By going to a lower density you save lots of money and lose very little insulating value if you look at the curves. Past the optimum, higher density offers less insulating value and cost much more.

Would it be feasible to use the Todol gun for filling

You need moisture to react with the foam. I don' tknow how easily it is done for a large area. Have you visited their tech page:

1. Can I make a thick section of foam? Yes. If a very thick block of foam is needed, we recommend that you lay in a

1 inch bead of foam and then mist water on top of the uncured foam; Do not put water on the top layer of foam, use this layering technique until the cavity is about half filled, the expansion of the foam will complete the filling.

How do one-part foams

Very well. One part foams will probably replace most of the two part foams over time. Less chemicals, easier disposal.

[SQLit]

I found this on the web awhile back. NO clue if they are reputable.

[Wayne Whitney]

Yes, they are one of the sources of two-part handifoam kits that I mentioned in my original post.

Any thoughts on one-part (moisture cure) foam versus two-part foam?

Thanks, Wayne

[Wayne Whitney]

Well, in two part polyurethane foams, I'm familiar with two classes of products:

1) Open-cell, semi-rigid products with a density of 0.5 lbs/ft^3, R-values from 3.6-4.0/inch, and perm ratings around 16 perms @ 3" thick. 2) Closed-cell, rigid products with a density of 1.75 lbs/ft^3 and R-values from 6.2-7.0/inch, and perm ratings around 1.26 perms @ 3" thick.

While the material cost of the closed-cell foams must be significantly higher, it seems like the installed cost/R-value is comparable to the open-cell foams. Is there any disadvantage to the closed-cell products?

Cheers, Wayne

[Edwin Pawlowski]

No disadvantages of closed, but with open, it may over time absorb moisture.