How to Repair Chimney Caps

A chimney cap is a metal "roof" that fits over the flue on top of your chimney. A chimney cap keeps rain and snow out of your flue. Wind or objects such as tree branches that blow into your chimney cap can cause damage that requires repair. If you think you can repair your chimney cap, here's how you can fix it.

Difficulty: Moderate

Instructions

1. Use a hammer or pliers to repair a bent chimney cap if it's made of steel or copper. If the damage is minimal, you can restore a damaged chimney cap.

2. Secure loosened or blown-off chimney caps by tightening screws or re-applying adhesive. Check manufacturer instructions for type of adhesive to use for the chimney cap you have.

3. Clean out any soot or debris from underneath the chimney cap. Most caps have a mesh or screening to deter animals or debris from getting into the chimney flue. If this mesh clogs, the chimney's draft is greatly reduced.

4. Repair any possible water leaks around the cap by caulking around the point where it meets the flue. Water can run down between the flue and brick of the chimney and cause water damage in your attic.

5. Chip away any damaged mortar if you have a mortar chimney cap using a hammer and cold chisel. Clean off debris and apply new mortar with a trowel, making sure the cap slopes away from the top of the flue as before.

Tips & Warnings

• If your chimney cap is made of anything but stainless steel or copper and it's over five years old and showing signs of rust, replace it. Stainless steel or copper caps usually come with lifetime warranties.
• Bring a tape measure when you go up on the roof to repair a chimney cap. If a replacement is necessary, you then have the ability to measure for a new one without having to go back down to get a tape measure.
• Check to see if your chimney has a chimney cap if your house was built prior to the 1980s. Most houses built before then didn't have chimney caps. Though not a necessity, chimney caps are a good idea.
• Check chimney caps once every year for potential repair.
• Wear safety glasses or goggles and gloves when chipping away old mortar from a mortar chimney cap.