Once the metal is in place.
Air seal attic chimney.
Fireplace flues are made from metal and over time repeated heating and cooling can cause the metal to warp or break creating a channel for air loss.
This horizontal air seal is known as fire blocking or draft stopping and it prevents the spread of fire between floors by sealing air spaces that permit its passage.
Set up a cordless drill with a.
Compare with other projects.
My natural gas furnace exhausts into a block.
Locate the main plumbing stack furnace flue or chimney and note this on your sketch for a reference point once you get into the attic.
It is essentially a sheet metal box that gets mounted into the opening through which the chimney passes.
Combined with attic insulation air sealing can help to alleviate the formation of dangerous ice dams in the winter.
Use the sheet metal to completely cover the chase.
View from within attic access.
Cut to the chase permalink.
Drop the attic door over the weather.
This is a result of moist air leaking into your attic and then freezing when it hits your cold attic.
Air seal and insulate your chimney to save money initial state of the chimney permalink.
Seal air leaks around fireplace chimneys furnaces and gas fired water heater vents with fire resistant materials such as sheet metal or sheetrock and furnace cement caulk.
Put on work gloves.
There will definitely not be cellulose in contact with the chimney.
Measure and cut the flashing for each side of the chimney using sheet metal cutters.
Seal small gaps with caulk up to inch and expandable foam spray up to 3 inches.
By air sealing in your attic you can stop many major air leaks and help to maintain the desired temperature throughout your home.
Pressurize your house once you re ready place a box fan in a window so it s blowing air into the house and close all the remaining windows and doors.
The support maintains a 1 inch airspace between the outside of the insulated chimney and everything outside of the support.
Access the attic through a crawl space in the ceiling using a stepladder or use or the attic stairs.
This isolated the masonry from an r 60 blanket of cellulose insulation that was blown in place after all the airsealing measures were implemented.
Cut a few pieces of foam board insulation the same size and screw them to the plywood with long 4 screws.
Install a piece of weather stripping around the access hole in the attic.
High temp sealant sheet metal and snips.
All you need to do is.
Just put it back into place.
Sealing an air leak around a chimney in the attic 1.