Slice a 1-inch-thick square from a three-string bale of straw. The dimensions of a bale of this type measure 12 inches by 12 inches from the side.
Stuff the square of straw into a large discarded T-shirt. Tuck the shirt's sleeves into the shirt, and roll the bottom of the shirt together and tuck it under one side.
Repeat Steps 1 and 2 with as many of these 12-by-12, 1-inch-thick squares of insulation you need. These panels can be slipped right into the framework of your home to replace fiberglass pads of the same size.