Fireplace FAQ Part 2

Q: My chimney was blocked by leaves or a bird's nest. Cleaning it up was a chore. How do I prevent this?

A: Get a chimney cap. Your home store will be able to sell you the right size chimney cap that will let smoke out but deflect leaves and discourage birds.

Q: What size chimney cap do I need?

A: Just measure the diameter of the flue on which you want to install it. Chimney caps are friction fit devices. If you have two flues close together, you can purchase a larger chimney cap that anchors to the chimney itself.

Q: Should I have my chimney sealed?

A: If you live in a wet climate, "sealing" the chimney can be worthwhile. Make sure you or the installer uses a product that is approved for this use. Ordinary sealant won't do. You need a special sealant that puts up a one way barrier. Water shouldn't be able to seep in, but it needs to be able to seep out. Otherwise, water on the inside of the chimney will be stuck there. This is especially a problem when the temperature dips below freezing. The stuck water will freeze, expand, and crack the chimney. This is called "spalling."

Q: I left the damper open when it was raining and now my fireplace has a bad odor. What should I do?

A: You've got some water behind the back wall of the fireplace. It's mixing with the ash and causing the odor. Cleaning it out is a messy job. You should call a chimney sweep. If you want to tackle it yourself, be prepared to get dirty. You'll need to reach through the damper and back to feel where the water is-about a foot to a foot and a half back. When you know where it is, run a shop vac back there and vacuum out all the water and ash. Remember to close the damper when not in use! You may also want to consider a top sealing fireplace damper with a gasket seal for added protection against this problem.

Q: Can I repair the mortar in my own fireplace? I've got some cracks I'd like to get rid of.

A: Yes, this is actually something you can do yourself. You can buy fireplace mortar in an easy to use caulking tube. Chisel away the old mortar. Spray the area with water to get rid of the dust and help the new mortar adhere. And apply the mortar. The first fire will cure it.

Q: How tall should my chimney be?

A: Your chimney should reach two feet above the tallest point on the roof within a 10 foot radius.

Q: How long should a prefab chimney last?

A: Many prefab chimneys are warranted for 25 years. As long as they are maintained, they should be relatively permanent and not need to be replaced for as long as you own the home.