Attic With No Air Sealing
There is some BATT insulation (all that pink) here, but not enough. Your insulation levels should be around R-49 (16 inches) in Maryland. On top of that, there is no air sealing. Insulation cannot work by itself as a thermal barrier, it needs air sealing to do its job effectively.
Sealing the Recessed Light Fixtures
Beneath the pink BATT, you can see how we have used a cover over the recessed light fixture. We then use caulk (the orange) to seal it properly. This way, the air can no longer escape through the lights. We use this method to seal any other attic penetrations that are allowing for air to pass through.
Blown-In Cellulose Insulation
After we have air sealed the attic, the next step is to insulate it properly. We use a blown-in cellulose insulation (the gray) because it is denser and more effective as a thermal barrier.
Crawl Space With Poor Liner
In this crawl space, there was an attempt at a vapor barrier, but that plastic liner on the bottom does not fully cover the ground and is basically doing nothing to prevent moisture from seeping up from the dirt floor.
Crawl Space Vapor Barrier
This is how a vapor barrier should be installed. Here we have a 6 mil vapor barrier that has been sealed with caulk across the walls and support columns. What you can't see is is how we removed the insulation in the ceiling, used spray foam to seal up the boards, and then re-installed the insulation. This will prevent cold air from creeping up into the addition.
