
What You Need to Know to Install a Chimney Cap –
You’re convinced. You really do need a chimney cap to keep the rain from damaging your chimney flue and to keep squirrels, raccoon, and bats from taking up residence. You have carefully measured your flue(s) and ordered the correct chimney cap. While you wait for it to arrive, give a few minutes thought to its installation. Here’s how to install chimney cap or caps:
First, if your chimney cap comes with directions from its manufacturer, follow them to the letter rather than use the general procedures below.
Chimney caps attach with four basic mechanisms: screws, chimney cap adhesive, high heat silicone, or friction fit.
Chimney caps can attach to four surfaces:
- inside the flue,
- outside of the flue,
- to the top of the chimney crown, or
- to the outside, vertical edges of the chimney.
The way your specific chimney cap attaches to flue or chimney depends on its style. See the instructions below to get installation directions on your type of chimney cap.
Note that chimney caps are made of sheet metal and may have sharp edges, so use protective gloves when you handle and install your chimney cap.
For How to Install Chimney Cap Instructions,
click on the type of chimney cap you will be installing.
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How to Install a Chimney Cap that Attaches to the Top of the Chimney | How to Install an Outside Mount Chimney Cap that Attaches to the Vertical Sides of the Chimney |
How to Install Chimney Cap That Fits Over One Flue
If you have a single flue chimney cap, the type that fits over the flue, just slip it onto the flue. It should cover the top 1 or 3 inches of the flue. Make sure there is at least 5 inches between the top of the chimney flue and the lid of the chimney cap to allow for good air flow. Now firmly tighten the screws on all sides of the chimney cap.
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Slip the chimney cap over the flue,
covering at least one inch of the flue,
and firmly tighten the screws (see the red arrows, above)
on all sides of the chimney cap.
How to Install an Inside Mount Chimney Cap for a Round Clay Tile Flue
If you have an inside mount chimney cap for a round clay tile flue, just push it down into the flue for a tight friction fit.
Then seal around the joint with a silicone sealer.
How to Install Chimney Cap with a Friction Fit, inside a Metal Flue
If you are installing a chimney cap inside a metal flue , push it firmly into the flue and seal with silicone sealer.
A chimney with two or more concentric metal pipes (an air-cooled flue) will need a special type of chimney cap that insures the cooling air properly flows from pipe to pipe. Insert such chimney caps into the inner most pipe. The collar should cover the outer most pipe.
To install an inside mount chimney cap
into a metal flue, just push the cap firmly into your flue.
To install a compression fit chimney cap, squeeze the overlapping parts on the bottom of the chimeny cap (as shown at left) and insert them into your flue. When you let go, the overlapping parts will spring tight open against the inside of your flue, securely holding the chimney cap in the flue.
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