You may be asking yourself, "Why do I need a chimney cap?"
Actually, there are a number of reasons!
Perhaps you've heard some strange noises coming from your chimney. Did you ever consider the possibility that it may be a raccoon, squirrel, bat, or birds? It very well could be! Those animals carry disease and, even worse, if small enough, can come right down the chimney and into your home!
It may sound harmless, but nesting material can cause carbon monoxide to build up in the house when the fireplace or wood stove is used. Nests may be built by birds, raccoons, sqirrels, etc. Once in your chimney, it is very difficult for these critters to get out, potentially dying while inside. This can produce maggots, flies and unpleasant odors in your home. Any nests in your chimney should be removed immediately before a chimney cap is installed.
Rain water can damage chimneys with stainless steel liners, chimney dampers, and mortar joints. Replacing these parts, once rusty, can be very costly. Rain will most likely produce mold and mildew as well. This makes for a bad smell throughout your home. On top of that, rain can also run down into the stovepipe and stove itself, causing even further damage.
If the wind in blowing in a certain direction, it can create a downdraft. In this case, if using a wood-burning fireplace at the time, the downdraft has the potential of blowing smoke back into your home. The flat shaped top of a chimney cap is designed to help prevent wind-induced downdrafts.
SPARKS AND EMBERS
While enjoying a warm fire in your home, you may see embers or sparks travel up the chimney. If they happen to land on the roof, they could very well produce a fire. A chimney cap is sometimes referred to as a "spark arrestor."
If a chimney cap is not in place, debris such as twigs, branches, leaves, etc. can build up inside.