Water down the chimney
We had a long soaking rain event this weekend in MA. I took the opportunity to do a careful leak exam on the interior of our reno (dryed-in but interior walls are still open).
The first and second floor fireplaces, both attached to the same tall chimney, had water running down the interior of chimney into both fireplaces. There were also signs of water leaking through the brick into the interior. I’ve never experienced this before with other chimneys. The chimney may be 100 years old, but it was inspected and determined to be sound.
Question … is the water entering at the top of the chimney or is it blowing through the substantial length of brick/mortar extending above the roof? The former could be remedied with a chimney top damper? If water is leaking through the brick / mortar, that would seem to mean flue gases could as well.
Cheers
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Replies
It may be you just got unlucky and had wind blow the rain in. That can happen when conditions are right.
I'd check your chimney cap though, and the morter around the top to make sure nothing is getting down between the brick and the liner. Sometimes these will crack and/or "chunk" apart and cause problems. There are masons who specialize in chimneys that can get this figured out and fixed pretty quickly.
Bill
Is there a saddle on the upslope part of the chimney? Sometimes this is not flashed properly, it doesn't take much to get a lot of water in through there. It also looks like the chimney needs tuckpointing as well which is not helping things.
As Bill said, a good mason can fix these.
The cap is newly installed. Its a long way up so I have not had eyes on it. Excuse to buy a drone? ;)
There is no saddle installed. I asked about this and was told to not worry about it. Hmmm.
The roof and flashing are new installs.
With the older houses here in snow country, if there is a chimney leak, it is almost always the upslope part. It doesn't take much snow to have 6" to 8" of buildup there. For a narrow chimney you don't need a saddle flashing but it also doesn't hurt.
Looking at the picture again, it looks like there is a bit of efflorescence on the back side of the chimney. If that is the case, this generally means water is getting in somewhere near the upper half not at the flashing.
Hey Akos. To which pic are you referring re: the efflorescence?
Looks like there are some white on the back corner of the chimney. Picture is not that good and maybe I'm seeing the flashing itself.
Hmmm. This is a corner of the house where it seems a lot rain water flows ... we have repaired water damaged siding, sheathing, and half of the corner post on this corner.