Capping your Fireplace and Chimney
Weather-stripping is important for your windows and doors. But just as important is the fireplace. The fireplace has the capability of sending voluminous amounts of war air into the chimney. Many fireplaces have a throat damper- an iron frame and door that opens and shuts the firebox. These slow down the leakage but are not sealed tight. Glass might work better, but it is also not ideal. The ideal seal for a fireplace is a chimney cap that is airtight.
Chimney caps are installed on top of the chimney and spring loaded so there is a tight seal. In order to open the lid a steel cable needs to be released. The cable will go from the damper at the top of the chimney, all the way to the fire box. Depending on how often you use your fireplace, the cap may need to be replaced after several years. If the cable fails or if there is a chimney fire, the lit will stay in open positon.
Chimney caps also keep out rain, prevent leaks and are important to the preservation of the masonry flue. They, in addition can prevent pests from entering, like squirrels and birds, and can stop downdrafts.
Choices of Sealing Dampers
At the home insulators we offer two different kinds of damper. Those with pop-up lids and those lids that pivot. The first usually comes made of stainless steel and cast aluminum, and has a chimney cap and a mesh animal guard. The second is made of aluminum, and can be fitted for both round and square flues. The two alike have silicon rubber seals and work just as well. The pivoting damper is less prominent and is more hidden from ground view.
Top sealing dampers also work for wood stoves or wood stove inserts in a fireplace. When this happens a round flue, usually stainless steel will be threaded through the throat damper in the fireplace. This leaves a significant hap around the outer area. Fireproof insulation can be used to stop air form escaping but a top-seal damper is a preferred seal.