Chimney Pipe Flashing/Boot for Metal Roofs

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Have your coworker post some pictures of that flashing installation. Maybe we can spot the issue?

FWIW, you are correct. There are many videos on the internet of poor quality flashing of metal chimney pipe on metal roofs. You can almost guarantee that within a few years these installations will be leaking.
 
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I have put in a request to get a picture from him before he fixed it with the second sheet. I figure you want to see what his cuts looked like, how the flashing slips in there, to see if that's where the issue was. He's on vacation so not sure if I'll get a response or not.

Really, his fix here is the same solution as the one in that Youtube video you just posted. It has that second sheet with the U-cut out of it and slips over. I do know that he said he bought "regular flashing", so definitely not Excel or something specific to metal roofs.
 

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I have put in a request to get a picture from him before he fixed it with the second sheet. I figure you want to see what his cuts looked like, how the flashing slips in there, to see if that's where the issue was. He's on vacation so not sure if I'll get a response or not.

Really, his fix here is the same solution as the one in that Youtube video you just posted. It has that second sheet with the U-cut out of it and slips over. I do know that he said he bought "regular flashing", so definitely not Excel or something specific to metal roofs.
If you have a sheet of the same metal roofing that is a great solution and is very easy to do. But as said many times before both Excell and ventis have very good instructions that go with their metal roof flashing. It really is not complicated
 
OK, that helps and explains his issues. The flashing is entirely under the roofing, which means there is an entry point below the flashing cone that is entirely dependent on caulking to keep water out. This is a common mistake. I'm not sure why he has the two bent up flaps below the flashing cone, but they look like an issue still. There should be nothing damming water as it flows down the roofing. That is why the proper flashing overlaps the roofing on the bottom edge, without a caulking dam of silicone there.
 
OK, that helps and explains his issues. The flashing is entirely under the roofing, which means there is an entry point below the flashing cone that is entirely dependent on caulking to keep water out. This is a common mistake. I'm not sure why he has the two bent up flaps below the flashing cone, but they look like an issue still. There should be nothing damming water as it flows down the roofing. That is why the proper flashing overlaps the roofing on the bottom edge, without a caulking dam of silicone there.
I think those tabs are to block the water from going in the ribs in the roofing. Took me a lot of zooming to come up with that
 
I think those tabs are to block the water from going in the ribs in the roofing. Took me a lot of zooming to come up with that
Yes and those ribs need to be under the flashing not ontop
 
So, did the place install mine correctly? They really gooped up the storm collar.

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I can't tell at all from that pic. But what in the hell did they do to that storm collar?

If you scroll up I have a couple other photos posted.

I can't tell you. Maybe wanted to make sure it didn't leak....?
 
If you scroll up I have a couple other photos posted.

I can't tell you. Maybe wanted to make sure it didn't leak....?
It looks decent. I just don't know why they used goop all over
 
Yes and those ribs need to be under the flashing not ontop
Just looked again, no wonder this poor fellow is dealing with leaks.
 
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Just looked again, no wonder this poor fellow is dealing with leaks.
Yeah really bad install. Sadly that is pretty common from metal roof guys here
 
Yeah really bad install. Sadly that is pretty common from metal roof guys here
Yes, I looked at some youtube videos for a good example and almost all were done incorrectly.
 
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Yes, I looked at some youtube videos for a good example and almost all were done incorrectly.
Yup many roofers seem to have forgotten that water runs down hill when it comes to flashing.
 
Yup many roofers seem to have forgotten that water runs down hill when it comes to flashing.
Not just roofers. I see this with window and door flashings too. Contractors want to rely too much on sealants instead of understanding nature and gravity. Water wants to flow downhill. Don't put obstructions in its path.
 
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I honestly don't know what's going on. He's a smart guy, and described his flashing install as cutting a hole and cutting the side slits half way down to slip the flashing under the top half sitting over the bottom half - like a shingled roof basically. He said that leaked every year until 2 months ago when he decided to add a whole 'nother sheet with a U cut slid over it.

But what I'm seeing appears to be flashing installed completely underneath the metal sheet roofing, the hole cut for the cone to pop up - which creates a spot for water to go under the metal roofing. Well I would expect that to leak eventually, totally dependent on caulking to protect that spot from allowing water under the roofing.

So I'm scratching my head over here. I don't know why he thought he was doing the side slits and slipping the flashing in there....that's not what I'm seeing.
 
I honestly don't know what's going on. He's a smart guy, and described his flashing install as cutting a hole and cutting the side slits half way down to slip the flashing under the top half sitting over the bottom half - like a shingled roof basically. He said that leaked every year until 2 months ago when he decided to add a whole 'nother sheet with a U cut slid over it.

But what I'm seeing appears to be flashing installed completely underneath the metal sheet roofing, the hole cut for the cone to pop up - which creates a spot for water to go under the metal roofing. Well I would expect that to leak eventually, totally dependent on caulking to protect that spot from allowing water under the roofing.

So I'm scratching my head over here. I don't know why he thought he was doing the side slits and slipping the flashing in there....that's not what I'm seeing.
put some of that on your rubber boot you might get 5 years out of it
 

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You are calling roofers ? Are there no chimney professionals in your area?

Yes, but they all use boots too. Also, I have most of the system installed. The only part left is to cut the hole in the roof, drop the chimney pipe in, screw down the fire stop, install the flashing and storm collar. If I wasn't afraid of heights it would have been done already.

Through the roof or geocell 4500 are much better.

Are you talking about the boot to pipe seal, or are you talking about the seal between the flashing and roof metal?