Recommended Woodburning Fireplace Installation Practices

1. LOCATION — The location of the fireplace in the house is extremely important. The fireplace chimney should be located on the upper 1/3 of the roof for optimal performance. Never locate the fireplace on the lower 1/3 due to reduced draft development by the chimney system and downdraft potential. A downdraft can cause smoke from your fireplace to spill into your home.

2. STACK EFFECT — “Stack Effect” is caused by warm air leaking out of your home through openings in the upper areas of the warm air envelope. When this happens, the lower levels of your home become depressurized. If your fireplace is located in this lower depressurized area, it will have a more difficult time drafting and it will smoke. You can minimize stack effect by eliminating upper level air leaks. This can be accomplished by using sealed can lights, sealing all upper level electrical junction boxes, and weather stripping all scuttle holes and stairway openings into the attic. And if possible, eliminate ductwork and air handlers located in the attic spaces, especially in cold climate areas. To further minimize the effects of upper level air leaks, you could introduce outside air into the lower level of your house.

3. WARM AIR ENVELOPE — A woodburning fireplace works best when it is completely located within the warm air envelope of the house. Installing a fireplace in a cold outside chase doesn’t pre-warm the chimney, which allows for immediate draft startup. An outside chase fireplace installation exaggerates stack effect since the chimney is always outside of the warm air envelope in a cold area.

These recommendations apply to both factory-built and masonry woodburning fireplaces. The majority of homes built in the 1800’s and early 1900’s followed the location rules outlined above. Back then, woodburning and coal burning appliances were primary heat sources and had to abide by the location rules in order to function properly. With the advent of super tight construction starting in the mid 1970’s, stack effect became a powerful force that all natural draft fireplaces and appliances would need to overcome. This created the need to tightly seal the upper areas of the warm air envelope.

If you have a location in your home in mind, such as a basement or at the bottom of a cathedral ceiling, where you cannot follow these rules, Heatilator®, Heat & Glo® and Quadra-Fire® offer a wide selection of authentic looking and efficient gas direct vent fireplaces. Gas direct vent fireplaces are not affected by location, stack effect or warm air envelope home design problems.

For further information, visit http://www.hpba.org/consumer/BestPracticesForWoodburning.pdf