We will be using dense pack cellulose for the wall insulation. Although the R value per inch is lower (R=3.5) then spray foam (R=6) it is much more environmentally friendly. It is 85% recycled newspaper (the average house will contain about 40 years worth or newspapers) and 15% Borate (a naturally occurring chemical that imparts mold, insect, and fire resistance/retardant properties).
We have borrowed an insulation blower (for the cellulose) from a friend. I can be seen here reaching into the hopper. Eli, Asa, and Grandpa Jim are collecting some cellulose that will be placed in the hopper.
Once the hopper is full it is turned on and 2 spinning mixers break up the cellulose. Asa can be seen here monitoring the hopper. A blower motor at the bottom of the mixer blows the cellulose through a tube and into the wall. Eli is operating the blower switch. We experimented with several methods. In the method above we screwed ply wood to the stud bays, drilled a hole in it, snaked a tube behind the plywood and filled the bay with insulation. The insulation packs so tight that you can remove the plywood and the insulation will remain. We decided that this method would require too much setup and too much wasted plywood. We opted for the method below.
This method requires stapling a special netting material very tightly across the studs. Then the insulation is blown between the netting and the exterior sheathing. This will allow us better visibility to ensure we achieve the proper insulation density. Eli operating the stapler, hey where's that kids ear protection. This process has just started and the upstairs is almost complete. Insulation won't happen for another couple weeks.
