Chimney Cap Airflow

There are actually two distinct though related factors affecting chimney performance.

Chimney cap airflow.

Unlike the wind directional tops the wind blocking chimney caps do not move with the airflow but instead are designed to increase the wind speed in order to create a partial vacuum. The same problem occurs if your house is located at the base of a mountain. It in turn ensures all the smoke smells and flue gas are pulled up and out of the chimney. Chimney caps that slip into the flue slip in chimney caps are designed to literally slide right into your flue.

Because they are so specialized they. Draft is the force behind flow while capacity is the capability to handle flow. When you brick up the fireplace you need to fit either an air brick or a plastic metal vent to allow air flow through the stack. This kind of chimney features two walls separated by open space and uses air to cool the flue.

R1003 9 3 rain caps where a masonry or metal rain cap is installed on a masonry chimney the net free area under the cap shall be not less than four times the net free area of the outlet of the chimney. Your csia certified chimney sweep can check your chimney and recommend any corrective action needed for proper draft and flow. Maintaining adequate airflow through your chimney is also critical for a well functioning fireplace. Before lighting a fire in your home you should always check your chimney for debris and other materials.

In fact having a plugged up chimney cap at the end of your chimney is like having a closed nozzle at the end of a hose preventing airflow through the chimney. Poor flow in a chimney can result from. Chimney caps reduce fire hazards and discourage backdrafts. Excessive creosote deposits closed or plugged dampers improper construction structural damage or even a dirty chimney cap.

The spark arrestor shall be accessible for cleaning and the screen or chimney cap shall be removable to allow for cleaning of the chimney flue. Many codes require a california home to have a chimney cap when it is sold or re roofed. Finally sometimes air actually blows down the chimney but less frequently than you d guess it s usually something else. Needless to say it s important to keep your fireplace chimney and wire mesh cap clean and regularly maintained.

A chimney needs a vent not just at the top provided by the cap but also at the bottom. You can then apply adhesive for a more secure fit. But maybe your chimney is short and next to a larger part of the house or a bigger building. Wind blocking copper caps.