If you want an easy way to temporarily block and unused fireplace flue to stop a draft you should consider installing a top sealing damper.
Block chimney draft.
The female end needs to be on the lower end.
Measure the width and height of the fireplace opening.
The lighter gases are buoyant and rise to be displaced by heavier ambient air.
Safety first step 2.
Operating a chimney damper.
If you want to permanently block a chimney the extreme solution would be to brick up the front of the fireplace or chimney breach tear down the chimney top and reroof over that.
Add a section of chimney piping.
Hire a professional to install a damper if you don t have one.
Replace the chimney cap and secure it.
If a chimney can not draft it will reach such high temperatures that will destroy glass doors cause flames to pour into the home and overheat any combustibles in the area.
How to block drafts from a fireplace method 1 of 3.
There was a lot of this done to old houses probably in.
Check your chimney step 3.
Check the draft and add a section.
What to do step 1.
Installing a top sealing damper will ensure the fireplace and chimney will make a 100 seal.
The draft is the pressure difference between ambient air and the less dense flue gases within the chimney.
Covering the fireplace with a draft guard.
A chimney s thermal performance provides the draft by maintaining a warm interior lining.
How to permanently block a chimney.
Bird nests fallen bricks frisbees leaves etc.
Secure the pipe into place with the correct screws.
Place the ladder against the side of your home and remove the cap on the chimney.
The center hole allows you to install chimney liner not included.
And accepts an 8 in.
Several styles are commercially available and many simply attach to the metal facing of your fireplace with magnets.
Install a damper or balloon.
Can block or partially block a chimney flue interfering with proper draft.
This way you or the next owner have the option to have it open or closed at will.
Top sealing dampers get installed at the top of the chimney and since the damper is far away from the fire it is able to have a gasket seal.
Since the damper is so close to the fire the damper is not able to make a 100 seal.