Chimney caps are an important component in the maintenance of your fireplace and chimney. But with a masonry chimney, you need to weigh thebad with the good. Below are some reasons chimney caps are a necessity:

1. A chimney cap keeps rain and subsequent moisture from building within your chimney.
2. A chimney cap keeps critters, especially birds, from establishing a home in your chimney.
3. A chimney cap improves the air draft of the chimney.
4. In the winter, a chimney cap helps keeps ice and snow from building up on the crown of the chimney, which will extend the life of the crown and minimize the chance of cracks.

Sounds like a no-brainer, so far, right? Not so fast. You must also consider the following potential down-sides of a chimney cap:

1. Bad draft. A poorly designed or improperly installed chimney cap can hamper air flow.
2. Permanence. Chimney caps can blow off if you live in areas with high wind.
3. Creosote build-up. Chimney caps can get clogged up, which will affect the performance of your fireplace.
4. They can be ugly. If your chimney is a prominent feature of your home, creosote, tar, and other discolorations are worth noting.

The lesson here is that you feel comfortable with the company you choose to install, maintain, or replace your chimney cap. A poor job or lack of care can have detrimental long-term effects. But when installed and serviced properly, the chimney cap is one of your best allies in fireplace maintenance.