Timing is Everything: When to Replace your Chimney Cap

Chimney caps are a lot like the topper on a Christmas tree, with one glaring difference—a chimney cap is much more than decoration. They’re vital organs to a chimney that should be well taken care of and replaced when needed.

Chimney caps come in many different designs, shapes and sizes. Just choosing the right one can be a chore sometimes. They’re generally made out of some kind of metal, whether it’s copper, stainless steel or galvanized steel. Some are better quality than others, and some look better than others. No matter which type of chimney cap you have, however, it should be inspected regularly and replaced when necessary.

Inspecting the Chimney Cap

Inspection of the chimney cap should occur right alongside your annual chimney inspection. If the cap becomes clogged with creosote or begins to come loose from the chimney, it can hinder the proper functioning of the chimney and/or allow unwanted things inside your chimney. The first thing to inspect is how securely the cap is attached to the structure. Generally speaking, caps that are screwed into the chimney crown coming loose should not be much of a problem. However, if not installed correctly using the appropriate masonry screws, the screws may begin to slowly back themselves out over time. As a result, the chimney cap may need to be re-secured via the correct methods and materials.

The next thing to inspect is the assembly of the chimney cap. Over time, whether it’s due to the weather, the heat of the chimney or animals, parts of the chimney cap may begin loosening. The metal top of the cap could have warped over the years and could be pulling away from the sides. If this is the case, it should be repaired or replaced. Sometimes, tightening or adding screws may also fix the problem.

Another thing to check is that the metal mesh is in good shape. Just because it’s there to keep birds and animals out doesn’t mean they won’t still try to get in. Hopefully, the mesh will be in good shape when one of your friendly neighborhood squirrels starts tugging at it. If not, it’ll eventually work its way in to the chimney liner. Also, creosote buildup can occur on the mesh, which can limit the airflow and hinder the chimney draft.

Lastly, you’ll want to check for rust. This shouldn’t be an issue with stainless steel or copper caps, however, the galvanized steel caps, which are of lower quality, will eventually begin to rust. These caps are usually treated with heat-resistant paint to hinder rusting, but the paint will eventually start to crack and peel, thereby enabling rust to set in. The best thing to do in this instance is to replace the chimney cap altogether, preferably with a stainless steel variety.

When to Replace your Chimney Cap

On draft-enhancing chimney caps (the ones with turbines), it’s very easy for the turbines to get clogged and stop turning altogether. If this is the case, the best thing to do is to replace the chimney cap. The turbines can be difficult to clean and will start clogging up more and more as time goes on.

If the mesh on the cap is heavily clogged or separating from the rest of the cap, the entire cap should be replaced. The mesh is one of the most important parts and should be kept in excellent condition. You never know when an animal will attempt to get in there by pulling at it. If it’s weak, the animal will be successful and you’ll have to call an animal removal specialist to get it out.

Any time you’ve had a chimney fire, the cap should be replaced. Chances are, it’ll be warped and damaged beyond recognition, leaving you no choice but to replace it. If your cap is on a metal chimney liner, and you’ve had a chimney fire, you’ll have to replace the liner as well as the cap.

The chimney cap protects the upper opening of your chimney and prevents rainwater, debris and animals from entering. Inspect it regularly and, if necessary, don’t be hesitant to have it replaced by a certified chimney sweep. The certified chimney professionals at Green City Pros can inspect your chimney and advise you on whether or not your cap needs replacing. Contact us at your earliest convenience to schedule an appointment!