I know what you mean about keeping insulation fluffy and not compressed. Ive installed a decent amount. Hate the stuff.
My walls are solid foam. The ceiling has lots of open space. Its maybe 5" thick and only has a little 2" flap of insulation laying on top. Thought i could spray additional insulation above the existing. Keep it fluffy and loose. Would have to reduce down the hose diameter.
Shoot....with all the existing speaker holes and ceiling vents. I could almost stuff insulation in there by hand. Cant really hurt. Wont be able to access every bay but thats ok. I could stuff a few handfuls in. Then push it back gently with a pole.
