Chimney caps not only protect the inside of your chimney but are also designed to protect the mortar crown area at the top of the chimney.
An uncapped chimney is an open invitation to birds and animals to “nest” inside your flue. These “nests” block your chimney flue and can result in a chimney fire.
How do I determine what kind of cap I need? Caps for chimneys come in many different styles and sizes. To determine what style is best for your application you will first need to know what kind of chimney you have.
If you have a single clay liner sticking out of your masonry chimney, measure the top of the clay liner. These dimensions will determine what size cap will be needed. The most common sizes for a residential home are 8×8, 8×13 and 13×13. But other sizes do exist, but these are the most common ones.
If you have multiple clay liners or no liner at all, determine the dimensions for a multi-flue cap. A multi-flue cap is mounted to the crown, so if there is no flue to attach it to, you can use concrete screws to attach it to the masonry.
Measuring for a Multi-Flue Cap. To measure for a custom cap, you will need the length and width of the crown. You will also need the height you want for the screen. You should have at least 8″ of clearance from the top of the cap to the top of the flue. So if your flue extends above the crown 4 inches, you should order a 12″ screen or cut down the flue.
All chimney caps, single or multi flue, can be made of either stainless steel or copper.