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