When you have issues with the performance of your fireplace, the cause often relates to the chimney whether it is the design, the installation, or the day-to-day operations. When you start a fire, it heats the air in the stack and rises because it is not as dense as the air outside. As the gas expands, it creates a draft which draws in clean air and ejects the gas outside of the home.
How Does A Chimney Draft Work?
A fireplace that has a poor draft allows smoke to enter your home instead of the chimney. This occurs for several reasons including the heat of the fire and the coolness of the fireplace or the chimney’s height that is a disproportionate measurement of a firebox to the piping diameter. Before you can fix the problem, you need to look for chimney draft problems. It will also be necessary to perform a chimney draft test to measure the direction of smoke and exhaust.
Factors That Affect Drafts
There are several chimney components that will lead to chimney draft problems including a block, structural damage, an unkempt chimney cap, incorrectly placed firebox, a closed damper, pesky animals, or improper installation. It is also possible that putting off repairs or not regularly cleaning out fireplace soot will lead to draft issues, horrible air quality, and dangerous fires.
The Firebox
Not caring correctly for your firebox will lead to two issues that affect a draft. First, a fireplace must be in harmony to function correctly. The ratio is one square inch of chimney flue to ten square firebox inches to release smoke and gas safely. Secondly, the placement must sit less than one inch from the back of the wall. It ensures that the exhaust has enough room to travel upward instead of outward. You must also practice safe fireplace practices by building it atop a grate.
How To Block A Chimney Draft
Before starting a repair, gather an extension ladder, bricks, piping, newspaper, and matches.
To Warm The Chimney Metal
- Light the end of a rolled newspaper and hold it under the flue to warm it.
- Make a fire in the firebox directly afterward to see if the draft is fixed.
Raising The Grate
- Put a brick under the legs of the grate.
- Start a fire and notice where the smoke goes (it should go to the flue).
- If that fixes the draft, you need to elevate the floor with a layer of bricks.
Raising The Height Of The Chimney
- Place the ladder against the side of your home and remove the cap on the chimney.
- Add a section of chimney piping. The female end needs to be on the lower end.
- Secure the pipe into place with the correct screws.
- Replace the chimney cap and secure it.
- Check the draft and add a section. Every two feet to ten feet improve the draft by 20%.
If you are unsure of where to begin, you can learn more about how we will help you on Facebook at www.facebook.com/NorthShoreRoofingMA or by calling (978) 977-3816.
