Chimney Caps

A chimney cap is placed on top of the chimney specifically to prevent birds and other animals from nesting in the chimney. Because they also often feature a rain lid to prevent rain or snow from going down the chimney. Therefore a metal wire mesh is often used as a spark arrestor. Additionally, the spark arrestor is also used to minimize burning debris from rising out of the chimney and making it onto the roof. Although the masonry inside the chimney can absorb a large amount of moisture which later evaporates. As a result, rainwater can be collected at the base of the chimney. Sometimes weep holes are placed at the bottom of the chimney to drain out collected water.

Wind Directional Chimney Caps

A wind-directional cap is a helmet-shaped chimney cap. Additionally, the cap rotates to align with the wind or airflow. Thus, preventing a downdraft of smoke and wind down the chimney. Other downdraft caps are based on the Venturi effect, solving downdraft problems by increasing the updraft constantly resulting in much higher fuel consumption.