My chimney into the fireplaces firebox

Q: Does precipitation ever present a problem if it comes down the chimney and lands on the Chimney Balloon? Does it matter if it is snow, rain or whatever?- EL

A: Dear EL, Precipitation of any kind does not affect the Chimney Balloon, but sunshine is not good for the Chimney Balloon.

The UV in sunshine will break-down the rubber retaining ring on the interior of the Chimney Balloon. That is the reason we use Viton retention rings if you are going to use a Chimney Balloon in a skylight chute to stop cold air from coming in around a skylight.

If you get a significant amount of precipitation in your chimney you may want to seriously consider a cap. The freezing and thawing of moisture in a chimney can cause problems with the tuck pointing and the bricks.

Q: Jason, Since I don’t live between the Tropics of Cancer and Capricorn, I don’t have to worry about the sun ever being directly overhead. So, UV from the sun is not a concern.

I don’t believe I have excessive precipitation as I live in New England in the US. But I do get some. I’m purchasing a house with many fireplaces. The heat is off this winter and I have noticed some small amounts of snow have accumulated in a couple of the fireplaces. So, my concern was about having this accumulation sitting on top of an inflated Chimney Balloon and eventually melting.- EL

A: I understand EL, Snow or rain will just sit on the top of the Chimney Balloon until it evaporates. It will not affect the material of the Chimney Balloon at all. – Jason