In this video, This Old House host Keven O'Connor assists in performing a whole-house energy audit.
1. Use an infrared camera to detect hot and cold areas around all doors, windows and walls on the first floor.
2. Go upstairs and use the camera to check along the corners between the walls and floors.
3. Also audit un-insulated partitions (interior walls) looking for areas that reveal cold air between the wall studs.
4. Put on a dust mask and work gloves, and climb into the attic to inspect the insulation.
5. Lift the insulation batts covering interior partitions. Look for any gaps and spaces between attic floor and the top plate of the partition.
6. Stuff fiberglass insulation into large gaps, then seal over the top with expanding foam insulation.
7. Wait for at least 20 minutes for the foam to harden, then lay the fiberglass batts back down on the attic floor.
8. Check where attic insulation meets the eave. Be sure it's not blocking the flow of fresh air from the soffit vents.
9. Cut cardboard baffles to fit between the roof rafters. Slip the baffles into place and staple them to the rafters.