Leak around Chimney and new flashing

#1

I’m having a leak problem around my chimney (where the chimney goes through the roof in my attic). I had the flashing replaced (copper) and it still leaked. Subsequently I had a Mason inspect the chimney. He did some minor re-pointing and applied water resistant silicon. However, he said the chimney and cap were in good shape (the home is only 15 years old). I had a different carpenter/roofer take another look at the flashing and they noted some areas on the copper flashing that should have been soldered, but had not been. They did the soldering and a couple days later we had 8 hours of heavy rain. The good news is the leaking was much less then previously experienced, but the bad news is there was still some leaking. Basically a few beads of water forming on the north side of the house at the area where chimney goes out of the attic and streaming down. Not heavy, but steady.

I this point I don’t know if it is still a problem with the flashing or if it is saturating through the bricks. The new counter flashing goes up from the roof about three feet so if its saturation, the water really has to travel quite far. This is quite frustrating.

I thought I’d reach out to see if anyone has any thoughts/suggestions. Thank you. I have attached a chimney3 photo.

#2

Difficult to see the flashing from this view. Always check the top of the flashing to make sure it is cut into the mortar or a counter flashing is installed. If no counter flashing, make sure it is securely caulked with a quality sealant. I have experienced leakage from the deck flange not being installed properly.

#3

Thanks, Donl. It does appear that the flashing was properly installed (cut into mortar, sealant, etc.). I’m hoping it is just small spot they missed soldering. They are coming back tomorrow to check it out. Temperature will be in the high teens tomorrow. Not crazy about them doing roof work in that weather, but they claim it is okay. Attached is another photo from the back which shows more of the flashing.

chimney2

#4

Tom, I have a few of my customers with masonry chimney’s call me and say that their chimney flashing was leaking. One guy was so mad that he threatened a lawsuit. This was after we replaced the flashing for the second time. We knew it wasn’t the flashing because it had been leaking before we replaced the roof and it still leaked after we did the replacement with new flashing. He called a fireplace company out and they told him that it was the flashing and not absorbing through the brick. So we water tested twice, once before we replaced the flashing for the second time and the second time he watched us sitting on his lawn chair. We soaked down the flashing only and no leaks. We then asked him if he wanted us to move up the chimney with the water and bam, it leaked within a few seconds. It can and will absorb through brick. The solution was a masonry sealer. No more leaks.

#5

Almost foolproof method for finding these kind of leaks, (nothing
With water is 100%). Tarp the chimney and leave flashing exposed. Go through a good rainstorm or two. Inspect attic area around chimney. These are very frustrating leaks if you have wind driven rain as they can literally blow water right in through brick or stucco. It would be nice if masons would put impervious membrane on chase and extending over flashing but it rarely happens.

#6

Very helpful. Thank you for responding. I’m in Connecticut and just waiting for some warmer weather so my Mason and Roofer can get up on the roof and we will do a hose/water test. The Mason suggested exactly what you said in order to find the source of the leak. I had the chimney water-proofed in December but the temperature was about 35 degrees. One chimney company told me that the brick water-proofing is not effective in cold weather and I should have it done again when temps are above 45 degrees. He also said I should have a rain cap installed as water can get in through the chimney flue. Do these suggestions make sense to you? Thanks again!

#7

Thank you for responding. My Mason/Roofer plan to use a garden hose to find the leak source (flashing or brick). Just need the weather to warm up some. As I responded to ContourRoofing earlier, I had the chimney water-proofed in December but the temperature was about 35 degrees. One chimney company told me that the brick water-proofing is not effective in cold weather and I should have it done again when temps are above 45 degrees. He also said I should have a rain cap installed as water can get in through the chimney flue. Thanks again for your thoughtful response.

#8

All good information. Make sure cap has some slope on it so water doesn’t just sit up there.

#9

Yes absolutely, I would put a masonry cap on the entire top instead of just a flue cap, then along with the water proofing of the chimney it should do the trick. The issue with masonry fireplaces is that the if the top crown is flat, it will hold water and eventually crack and lead to moisture penetration. Also, a masonry cap typically doesn’t have a pan on the top but more like a cover so there shouldn’t be any concern as to a slope on it as Tileman says. Here is what we install on masonry fireplaces. As you can see there is no center pan just the sides and a top cover.

#10

Contour,
That is a nice detail and I haven’t seen them in our area. Typically we see a decorative shroud with a pan covering top of fireplace with a slight pitch built into it. I like your detail better.

#11

Ok yeah we have those on framed up chases with siding but on masonry we use these. We have a metal shop that fabricates these along with the pans and shrouds for us. Super simple to install.

#12

Thanks for the photo. Very helpful. I just went to your web site hoping you were near Connecticut. Unfortunately, your not. Would love to hire a guy like you. You and Tileman have been very generous with your expert advice and I appreciate it. If you happen to know of anyone in CT area that does great work, please let me know.

#13

Hi Tileman - Don’t know your location. Do you do work in Connecticut?

#14

Hey TomG, I wish I could help. If you have any additional questions, please feel free to email me at cory@contourroofing.com.

#15

Pretty much the opposite end of the country Tom.
We’re in Southern Oregon.

#16

Update - Thank’s guys for posting. In the end, it looks like water-proofing and new chimney cap did the trick. We have had some serious heavy rain this spring and no leak.

Very best,
Tom

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#17

If you tarp a chimney make sure to not cover a flue connected to any gas appliances such as furnace or water heater, or you may never hear from that customer again.

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