How to Tell If a Wall Has Insulation
- 1). Turn off the power to the wall you want to inspect at the circuit breaker. If you are not sure what breaker controls that room, turn off the main breaker.
- 2). Locate a light switch or electrical socket on the wall.
- 3). Remove the screws that secure the cover plate with a screwdriver. Take the cover plate off the wall.
- 4). Turn on your flashlight and shine it up into the hole in the wall. Look for pink or yellow fiberglass material inside the wall--this is insulation. If the wall appears hollow and dark and you do not see anything, the wall does not have insulation in it.
- 5). Replace the light switch or outlet cover and secure it with the screws. Turn the power back to the room back on.
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