[Christ]

Thanks! I plan on making that thread into a sort of itemized list to show people who are looking at it exactly what they're throwing away... and what they could be doing with it! Everything anyone can think of that is a re-use for ANYTHING will add to it.

Ben - for a Garage, one of the first steps is to seal up the drafty bits. There is no point in giving it any kind of heat if you can't contain the heat you're providing.

Anything can really be used for insulation, the idea is to get as many small, immobile air bubbles as you can between the inside and the outside. Any type of reactive foam will help with this, as it forms stationary air bubbles as it dries. Common myth is that density is a good thing in insulations - it's not. Just stuffing R34 on top of R34 is actually HARMING your efficiency... the stuff is at a specific density already, so that it operates near it's peak efficiency when installed into a properly sized gap.

If you're really interested in recycling, you can make your own insulation easily - Your local salvation army office throws away (that's right, even the SA throws lots of stuff away) any donation that isn't "suitable" for sale or charity. Most of that "stuff" is old clothes that might have holes, etc in them. Give them a call. They probably won't just give you the stuff, but you can get it REALLY cheaply... cents per pound cheap.

Shredding denim (a great insulator) into a grainy powderish consistency yields excellent insulation results.

If you do plan on just insulating and working on what you already have, but making your own insulation isn't for you, I would caution you to stay away from Fiberglass insulation. When you breathe the stuff in, it sticks in your alveoli. It NEVER comes back out. It's very unhealthy for anyone exposed to it. Instead, try carded wool from sheep! Living in Wisconsin, I'm sure there are plenty of sheep, goats, and alpaca near you, you might be able to buy "seconds" of wool very cheaply. Remember to card/wash it and air it out though!

You may also be able to just buy wool insulation. If that's the case, it's usually pretty economical... comparable to fiberglass.