How to Spray Polyurethane Foam Insulation
- 1). Cover nearby electrical outlets and circuit breakers with masking tape. This will stop the polyurethane foam from getting in the sockets where it can cause unwanted electrical problems.
- 2). Open the polyurethane spray foam insulation kit. In addition to the chemical tanks that store the foam, many kits will include a hose and a variety of nozzle attachments.
- 3). Put on protective gear before handling the foam insulation kit. When dealing with spray chemicals it's always a good idea to put on goggles, gloves and a mask to cover your nose and mouth. Wearing coveralls would also be a good idea to avoid getting any foam on your clothing.
- 4). Set up the spray foam apparatus. First, plug one end of the hose into the chemical tank and make sure the connection is secure. You might want to use some extra making tape to ensure there is a tight seal between the hose and the chemical tank. Next, choose an appropriate nozzle and attach it to the other end of the hose.
- 5). Test the apparatus by spraying some of the foam on a practice surface. Performing this test will give you a good idea of how fast the foam shoots out of the nozzle and the degree to which it expands. It can also draw your attention to any errors that might have been made during setup.
- 6). Spray the foam on the area you want to have insulated. Hold the nozzle roughly 20 to 30 inches from the surface and spray in a side-to-side motion. If insulating the walls of a house, start at the top of the wall and try to spray the foam evenly between the two-by-four wall studs as you work your way down. Keep in mind, it's all right if some excess foam sticks out past the wall studs because it can easily be removed later.
- 7). Go back and examine the surface after the foam has had time to fully expand. If you notice any gaps in the insulation, spray more foam to fill them in.
- 8). Skim off excess insulation by using a hand saw to cut away any of the foam that sticks out past the wall studs. Failure to remove excess insulation could result in problems later if you intend on installing drywall.
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