DIY Foam Home Insulation
- 1). Conduct a test spray on one section of the wall, preferably in a corner. Spray just a little of the foam into the wall to see how far it expands. Foams will expand up to 100 times its size when in liquid form. Continue to spray the directly on the wall until you have a very good idea of how much the spray foam expands and are used to working with the equipment.
- 2). Spray the foam on the wall aiming between the studs and working the spray hose back and forth slightly. Allow the foam to expand to fill in the entire area, but do not spray so much foam in one spot that it expands out beyond the edge of the 2-by-4 studs. Do not spray over the studs, just between them.
- 3). Let the foam set for at least an hour. Use a hand saw to cut away any foam that has expanded beyond the edge of the 2-by-4 boards.
- 4). Repeat steps three and four until the entire wall is covered.
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