It is an effective barrier to the passage of heat.
Insulation around brick chimney in attic.
If there is a straight open space accessible from above you might consider polyisocyanurate foam insulation.
Spun fiberglass insulation is like a sponge as far as its ability to collect and hold significant volume of water.
For diy attic insulation you ve got two choices.
In hot climates it prevents heat from outside the house entering reducing the need to use air conditioners.
Insulating your crawl space walls with at least an r 19 or r 21 will go a long way.
A 2 inch board has r 13 insulation.
The b vent system requires air space clearance as well as clearance from combustibles.
They make 4 wide blanket sized insulation for this.
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.
Once you ve decided which type is best for you examine the material options and prices to home in on the right product.
The opening around a furnace or water heater lue or chimney can be a major source of warm air moving in the attic.
You might want to consider a wireless thermostat.
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.
Both can be added to uninsulated attics or layered over existing material.
Fiberglass insulation is commonly used in attics around the chimney stack.
In either cse it fills the required open air space around the b vent in the un conditioned attic space.
It may be easier to use rigid foam insulation than.
Fiberglass is one of the most commonly used materials for insulating the home.
Loose fill or batt the common term for blanket insulation.
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.