Sealing the Attic Part 2

So, to get to the nitty gritty, I began sealing.

The recommended way is to use “Great Stuff”. This is an expandable foam in a can with a spray tube.

It’s a messy, glue-like substance that works well and is a bit finnickly as a product. For example, once you begin using it, it is recommended that you use up the whole can. Also, you have to hold the can upside down so the as stays above the product, of else you get gas blows and no foam. Finally, the tube falls off fairly easily becomming a hastle when you are stretching into the eaves of the house. Use rubber gloves, eye protection and old long sleve clothes. I have a few bald spots on my arms where I had to cut the foam from my hair.

So, over several months , I probably used 15 cans of this stuff and sealed the devil out of all of the cracks, pipe holes and wire holes.

 Basically, I went into the floor below and noted all of the walls. Main walls, closets etc. I also noted where the lights are. Then, methodically, I lifted the fiberglass insulation where the walls were and filled in the various gaps and holes wherever I found them.

One tip is to let the foam dry before replacing te insulation as the insulation will stick to it. Also, try to spray only small amounts of the foam as it expands greatly.

I did have some struggles in the attic. Sometimes, there was a wall top that had a larger board placed over it. In essence, the gaps were covered by the board. In this case, I sealed the larger board surfaces. Also, Sometimes, the floor joists sometimes overlapped and did not meet perfectly (there was a gap between them). In this case I foamed all of the cracks in the area I could find.

Wherever there was an area where I had a doubt that air could move along some interface between either a ceiling and a board, or two boards, I foamed a longer run of the area. For example, against the outer walls (where the structure of the house is a wall and not a roof), I foamed  the wall top plate, but also foamed up the stud interface for 1-2 feet to optimize my chances of a good seal.

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