Insulation Around Brick Chimney In Attic

The b vent system requires air space clearance as well as clearance from combustibles.

Insulation around brick chimney in attic.

If there is a straight open space accessible from above you might consider polyisocyanurate foam insulation. Insulating your crawl space walls with at least an r 19 or r 21 will go a long way. They make 4 wide blanket sized insulation for this. For diy attic insulation you ve got two choices.

Seal between the chimney and the framing with fireblock foam or caulk to prevent exterior air from coming in and then put 3 of roxul directly against the chimney brick. In either cse it fills the required open air space around the b vent in the un conditioned attic space. In hot climates it prevents heat from outside the house entering reducing the need to use air conditioners. If the chimney is an older brick one it may be possible to insulate it along the warm side at the same time as the walls of the knee wall spaces.

Go with a full aluminum sheath right against the chimney to serve as the air barrier and then fill in behind it with roxul or 2. Because the pipe gets hot building codes usually require 1 inch of clearance from metal lues 2 inches from masonry chimneys to any combustible material including insulation. You might want to consider a wireless thermostat. It is an effective barrier to the passage of heat.

Both can be added to uninsulated attics or layered over existing material. You will probably have to look somewhere besides the big box stores for this. A 2 inch board has r 13 insulation. Spun fiberglass insulation is like a sponge as far as its ability to collect and hold significant volume of water.

Fiberglass insulation is commonly used in attics around the chimney stack. I think i ll either. It may be easier to use rigid foam insulation than. Once you ve decided which type is best for you examine the material options and prices to home in on the right product.