How To Seal Around Chimney In Attic

Of course you ll still need to seal gaps with fireproof caulk.

How to seal around chimney in attic.

The bricks go up around the tile flue liners but at the top you need something to stop the rain and snow from just falling in around the tiles. All you need to do is. I used pieces of various widths up to 6 in. The opening around a furnace or water heater flue or chimney can be a major source of warm air moving into the attic.

Seal around furnace flues. I installed it upside down with the drop leg pointing up. The same rules apply to prefabricated metal chimneys. Set up a cordless drill with a.

Cut a piece of plywood to the size of your attic door. Plug the big holes first. Access the attic through a crawl space in the ceiling using a stepladder or use or the attic stairs. Long piece from a batt of unfaced fiberglass insulation and fold it at the bottom of a 13 gallon.

Cut a few pieces of foam board insulation the same size and screw them to the plywood with long 4 screws. Put on work gloves. 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. 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.

In places to seal the airspace between the ceiling joists and the chimney as shown in the drawing. Drop the attic door over the weather. Sealing an air leak around a chimney in the attic 1. This folded leg strengthens the unsupported edge and created a perfect little trough for firestop caulk.

Finally prepare for adding insulation foam or. You can see that the very purpose of the chimney crown is to keep rain out. Wrap insulation in plastic. 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.

2 many chimney leaks are from cracks in the chimney crown. Plug open stud cavities. Measure and cut the flashing for each side of the chimney using sheet metal cutters. 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.