71: Soythane Foam

Soythane foam comes in double canisters, pic 1 and is sprayed with an air gun, pic 2. There are six canisters per case (about $140), each case is supposed to cover about 200 sq ft (foam 1" thick), so each canister covers about 33 sq ft. Cost wise this is about 70 cents per sq ft, about the same as method 2 in previous post and cheaper than method 1. The only equipment you need is a compressor capable of 10 cfm at 100 psi. For those of you who have never used anything larger than a small home size compressor, this turns out to be a rather large compressor. More on that later.

As I'm spraying the roof first, let's envision what that will look like. First, I'll be standing on a ladder or on a walkboard on scaffolds. I'm suited up in a full body suit (Tyvek), with goggles, respirator, rubber gloves, ear plugs, hat. The gun and a full canister weigh in at what I've been told is 17 lbs, though it feels heavier. Turn on the air to the atomizer and mash the trigger and spray out the canister contents in 45 or so seconds. Discard canister, load another, repeat.

Initially, I thought this canister idea was a little wasteful, and would likely result in this stuff costing more than it should. But, there are some nice advantages to this method of delivery. Foam doesn't go through the gun and there are no long (heavy) hoses full of foam to drag around or purge, clean up and stow at the end of the day. Unlike the Source of Supply method above, this system has been around for a long time, as this gun also gets used to spray bed liners in pickup trucks. So, this equipment has some history.

The company advises that if you're going for 2 or 3 inches of finished foam thickness, to do it all in one pass instead of three separate 1" layers. This stuff generates heat when curing and more heat means more expansion (thicker foam layer). Since I want about 3" thickness that means each canister will only be covering about 11 sq ft of area. My roof trusses are 4 feet apart, so I'll spray truss to truss by almost 3 ft per canister. Doing that much area, I can realistically do it from a stationary position on a ladder. Spray, move ladder, reload gun, spray next area.

You will want a table nearby with your spare cartridges, so you don't have to bend over and pick them up off the floor. You will use the table to screw the mixing tube on top of each canister before you put the canister in the gun and then attach the atomizer hose. You will also want a couple of empty boxes. The foam comes in boxes so you have plenty of those already. Box 1 is for the empty cartridges and box 2 is your emergency box to put malfunctioning cartridges in. More on this in next post.