Common Chimney Questions & Answers

Q. How often does my chimney really need cleaned?

A. Some homeowners suggest having a chimney professionally inspected, cleaned and swept every couple of years. However, the National Fire Protection Association says that chimney and fireplaces should be inspected at least once per year. You may think that because you do not use your chimney, it doesn’t need a professional’s touch. Unfortunately, this is not true: animals, birds, and rodents may have nested in your chimney without your awareness, causing blockage. (Even if you use a gas fireplace, follow the same caution as above.)

Q. How Do I Clean My Own Chimney?

A. If you believe that your chimney needs sweeping, it can be a DIY job. The first thing to do is to invest in a set of chimney rods and a brush: The rods screw together to form a longer, stiff yet bendable pole; the brush is usually made up of thicker, metal barbs.

Now comes the actual sweeping. Before covering the fireplace opening with plastic—as soot will fall during cleaning—open the damper, or the metal door above the firebox. Wearing safety glasses and old clothes, take your chimney sweeper and climb up on your roof. Remove the chimney cap, often made of copper, black- or stainless-steel.

Following this, push the sweeper down the chimney in an up-and-down motion making sure to clean the entire chimney. When you’re finished, go back indoors and (if you have a wood burning stove) clean the chimney and flue with a shorter brush. Finally, reach up into the damper with a vacuum and remove the deposits of soot, also making sure to clean the fireplace and walls around it. Your chimney is now ready for the perfect warm blaze.

Q. Why Does My Chimney Stink?

A. If you haven’t completed cleaning your chimney, then the smell is most likely one of two causes. The first is probably coming from the buildup of creosote—a gummed, tar substance from excessive wood burning. Because of air pressure being heavier outdoors than in, air is forced down the chimney and you then get the smell in your house.

To help keep the air out, you can either install a new chimney cap or a new damper. If you replace both and there’s still a stench, you may need to clean the chimney with a chemically scented treatment. However, if this is not the problem, you may have a dead animal that became trapped in the chimney while nesting and is decomposing, causing the odor.

Q. There’s Water, So Is My Chimney Leaking? And Where?

A. The water you’re noticing may be the chimney, around the chimney, or even a leaky roof. If, however, you’re certain it’s your chimney that is leaking, the water could be coming from a number of places exposed to the outdoors. The first place to look is the chimney crown, which lies directly at the opening of the chimney. After checking the crown, check the chimney cap (a copper or steel covering) for cracks or damage.

If there are no flaws, check the chimney flashing, which is attached directly where the chimney comes out of the roof. This is usually a thin metal sheet protecting the chimney and flue from water. If these chimney parts do not look damaged, then water may be soaking slowly through cracked bricks. Replacing your chimney components should keep rainwater out. If all else fails, make sure to check your roof for possible leaks.

Q. How Do I Buy the Correct Chimney Cap?

A. The easiest way to install a chimney cap is the kind with four pressure screws on each side. This allows you to place the cap over the top of the flue and tighten it. This single-flue cap is designed for one flue at a time while a multi-flue cap covers more than one flue at a time. The best way to know which flue you need is to measure the diameter of the flue, and then go to the hardware store with these measurements. If you have more than one extending flue, and they are more than 6-8 inches apart, you can use a single-flue chimney cap for each one.