How To Seal Around Chimney In Attic

Because the pipe gets hot building codes usually require 1 inch of clearance from metal flues 2 inches from masonry chimneys to any combustible material including insulation.

How to seal around chimney in attic. Measure and cut the flashing for each side of the chimney using sheet metal cutters. Drop the attic door over the weather. Install a piece of weather stripping around the access hole in the attic. Cut a piece of plywood to the size of your attic door.

Plug open stud cavities. Wrap insulation in plastic. Of course you ll still need to seal gaps with fireproof caulk. Access the attic through a crawl space in the ceiling using a stepladder or use or the attic stairs.

The chimney crown is the cement part on top of the chimney. I installed it upside down with the drop leg pointing up. Long piece from a batt of unfaced fiberglass insulation and fold it at the bottom of a 13 gallon. 2 many chimney leaks are from cracks in the chimney crown.

You can see that the very purpose of the chimney crown is to keep rain out. Apply a thick bead of high temperature caulk the flue on one. The metal and caulk method you describe is one that i typically use in attics but an alternative approach is to frame tightly around the chimney with steel studs then use solid steel channel at the top as a fire block. All you need to do is.

The opening around a furnace or water heater flue or chimney can be a major source of warm air moving into the attic. Finally prepare for adding insulation foam or. Put on work gloves. Sealing an air leak around a chimney in the attic 1.

Set up a cordless drill with a. Once the metal is in place seal the remaining gap between the metal s edge and the chimney with a thin bead of high temperature silicone caulk. Plug the big holes first. In places to seal the airspace between the ceiling joists and the chimney as shown in the drawing.

The same rules apply to prefabricated metal chimneys. Remove the insulation between the joists where the flue is located to clear an area about 18 inches away from the flue on each side. Seal around furnace flues. Cut a few pieces of foam board insulation the same size and screw them to the plywood with long 4 screws.