How to Install a Chimney Cap

If your home was built after 1980, chances are you already have a chimney cap. However, older houses were not required to have these caps installed. Caps prevent snow, rain, and debris from coming down the chimney, and sparks from coming out of the chimney.

In most cases you can install the chimney cap without help as long as you are comfortable working on the roof. Keep in mind that you must go onto your roof twice: once to measure the top of chimney and again to install the chimney cap. When purchasing a chimney cap, choose a copper or stainless steel cap that will not rust. Most also come with lifetime warranties.

You can also paint the chimney cap or seal it before installing it. Copper chimney caps can be sealed to prevent the natural aging process: just be sure to use a sealant that will withstand heat. Stainless steel can be painted any color: you can also purchase a powder coated stainless steel chimney cap.

Step 1: Measure the opening of the chimney with a tape measure and purchase a correctly sized cap. To prevent sparks from hitting the roof, you can purchase a spark arrestor cap, which will reduce the possibility of a roof fire.

Step 2: Place the chimney cap over the flue and consequently the top of the chimney.

Step 3: Tighten the screws that hold the base of the chimney cap to the top of the flue. The tension screws should each be tightened a little bit at a time, to ensure that no one screw is bearing the whole weight of the chimney cap base.

Step 4: Make sure that the screen and any holes in the base are clear of packing material and other obstructions.

Step 5: Caulk around the chimney base and the crack between the flue to prevent water from trickling into the attic.

Step 6: Screw the top of the chimney cap to the chimney base.