Chimney Screen

A chimney screen is a cover for your chimney and performs several functions, most importantly on a fireplace flue. The screen on the chimney is a spark arrester that prevents large embers from starting a fire on your roof or your neighbor’s. It’s a code violation not to have on in Harper Woods and other communities.

A properly installed chimney screen also prevents animals from using your warm chimney as a winter residence. But a desperate raccoon will tear a chimney screen off when searching for refuge from the elements.

If you purchase a prefab chimney screen, it may come with a metal roof that prevents water from entering the chimney and rusting out the damper.

Some city codes require the chimney screen to be four times the surface area of the flue. The holes in the mesh have to be no larger than 1/2-inch and no smaller than 3/8-inch.

The reason for the screen being four times larger than the opening on the chimney is that a flat screen lay directly on the crock could build up with leaves clogging the airflow.

With this in mind we can make a chimney screen out of 1/2-inch galvanized welded wire screening, called hardware cloth. It is that meets the criteria of our local codes. We cut a piece of it 15-inches larger than the chimney flue protruding out of the chimney. Then cut 7 1/2-inch squares out of each corner so the four flaps of mesh can be folded to make a box. Secure the wire mesh box to the crock using banding iron strap and a long bolt like a large hose clamp.

This homemade one costs $8 compared to $25 for a store bought one. The advantage of the store bought screen is it will have a roof that also prevents water damage.