Newly constructed chimneys today are required by law to have a flue liner. They’re not, however, required to also have a chimney cap to protect the chimney. Many chimneys are operated without any kind of covering over the top of the flue, and in every case, trouble is sure to come around sooner or later.
What is a chimney cap?
There are actually two types of components that cover a chimney flue: chimney caps and flue covers. Either type will protect the flue, but a proper full-width chimney cap also covers and protects the vulnerable chimney crown.
Both caps and covers have solid tops and open (usually mesh) sides to allow smoke to leave the chimney. Because chimney caps are the more protective of the two components, It’s important to understand their purpose
6 ways chimney caps protect chimneys
Keep out rain and snow
Without a covering, your chimney flue is open to however much rain and snow is in the air. Moisture inside the flue can damage the chimney liner and fireplace damper through rusting and erosion. Additionally, flue moisture is a common cause of mold outbreaks, which can be dangerous to people and pets.
Prevent animal infestation
Small animals such as squirrels, birds, rodents and raccoons often seek shelter inside chimneys. With no chimney cap, it’s like putting out a welcome mat for them. The nests some of these animals build can cause a drafting obstruction and serve as fuel for a chimney fire. Animals that die inside the flue cause these same problems along with unpleasant odors that will drift into your home.
Depending on where your chimney is situated, it may be in the line of falling leaves, twigs, fruit and nuts from nearby trees. This debris, as with nesting materials, will cause a dangerous drafting obstruction. A narrowed flue passage can send smoke and deadly carbon monoxide into your home and put the health of people and pets at risk.
Help to prevent downdrafts
A secure chimney cap is an excellent wind block and helps to prevent wind-based downdrafts that can blow smoke, ash and fiery embers and sparks into your home.
Contain ascending sparks and embers
If there’s no contrary airflow, sparks and embers will rise into the flue during a fire. Depending on their velocity, these particles can exit the flue opening and land on the roof or in the yard. A chimney cap is the best way to keep this from happening.
Protect concrete chimney crowns
A full-width chimney cap keeps water away from the chimney crown. Rain and melting snow can easily get into the small cracks often found in chimney crowns and cause serious problems. Once the crown is broken open, water can move into interior spaces within the flue and inflict system-wide damage.
Have a chimney cap installed
If you’ve been running your fireplace/chimney system without a cap, now is the time to have one installed. The relatively small investment can pay for itself many times over by preventing chimney damage, smoke backups and fires.
Fluesbrothers Chimney & Fireplace of Kansas City, KS, is here to help you keep your chimney safe and fully functional. We install custom full-width chimney caps that protect your chimney and look great while doing it.
Get your questions answered or schedule an appointment by calling (913) 236-7141.