How do you close a fireplace?
If you have a damper in the fireplace there should be a handle that will allow you to close this damper or metal flapper. If the damper or metal flapper is missing, damaged or broken you can get parts to fix it or you can install a chimney balloon to plug the chimney at the bottom or a chimney top damper to plug it at the top. Chimney top dampers work well to stop birds, bugs and vermin from entering the top of the chimney. A Chimney balloon is not as expensive and will stop air and odor from passing through the chimney into the living area. ---- Note: Some gas log fireplaces have the damper disabled or removed because of the building code requirement for gas log fireplaces that was started in the 1990s. The reason for this code is to prevent a homeowner from asphixiating the occupants of the home by using the gas log without opening the damper. The downside of this code is you are loosing inside heat or air conditioned air constantly through the chimney. If this is the case with your gas log the only way you can plug your flue is with a chimney balloon since it is not a permanant mechanical damper.