Chimney thru metal roof

[jeff_t]

We bought a vacation place a few weeks ago, and I have a stove to install. Some brief searching hasn't shown me much for what to use to penetrate a metal roof. I found a silicone boot from Selkirk, but I'm not sure if that's what I need. We're taking a U-Haul full of crap in a couple of weeks, and I may be able to get the stove in, if I can gather what I need in time.

It isn't corrugated, it looks like this. I think. I have only seen it once when it wasn't snow covered.

 

[topoftheriver]

We bought a vacation place a few weeks ago, and I have a stove to install. Some brief searching hasn't shown me much for what to use to penetrate a metal roof. I found a silicone boot from Selkirk, but I'm not sure if that's what I need. We're taking a U-Haul full of crap in a couple of weeks, and I may be able to get the stove in, if I can gather what I need in time.

It isn't corrugated, it looks like this. I think. I have only seen it once when it wasn't snow covered.

View attachment 91930

If you're not sure, it would be wise to hire a professional so you don't damage the roofing. It is tricky to get the hole in the right spot.

 

[jeff_t]

I have done two installs through shingled roofs, so I'm pretty familiar with the process. I'm just not sure how to seal up the metal roofing.

 

[begreen]

I think you'll want to use the special flashing/boot for that job. Here's an article on how to and not to do this. Ping Hogwildz. He knows all things roofing.

http://www.mbci.com/pdf/published_articles/metalmagPipe_200507_final.pdf

 

[jeff_t]

I think you'll want to use the special flashing/boot for that job. Here's an article on how to and not to do this. Ping Hogwildz. He knows all things roofing.

http://www.mbci.com/pdf/published_articles/metalmagPipe_200507_final.pdf

Thanks.

I can see this won't get done in an already sorta busy weekend. I think I better put it off until summer.

 

[begreen]

Good idea, this is not a job you want to rush. Most importantly, remember that water wants to run downhill. Don't impede it by creating artificial dams of silicone where it isn't needed.

 

[jeff_t]

Good point. There's not much pitch to begin with.

The previous owners left us with 68% in the 500 gal pig . No hurry, I guess. Probably should buy some wood, though.

 

[Leroy_B]

I'm going to follow this thread closely. I also wondered about a chimney flashing for a metal roof and how the install is done without any water damming up.

 

[webby3650]

I know some people use the silicone flashings with success, but I often find them leaking. In addition to the risk of leaking, they offer NO support for the chimney like a metal flashing offers.
Anytime we do a metal roof install we use this one from ICC. It offers a permanent seal, it installs similar to a shingle type flashing, by tucking under the metal on the top side.

Here is the flashing to use: (broken link removed to http://www.icc-rsf.com/main.php?t=chem_produits&i=95&l=en)

 

[Treacherous]

I have this one. No complaints here.

Anytime we do a metal roof install we use this one from ICC. It offers a permanent seal, it installs similar to a shingle type flashing, by tucking under the metal on the top side.

Here is the flashing to use: (broken link removed to http://www.icc-rsf.com/main.php?t=chem_produits&i=95&l=en)

 

[jeff_t]

Maybe we should think about tearing the brick chimney down and go thru the wall. There is a ceiling support in place from a previous metal chimney, but they covered the hole when they put the new roof on. The exit point has to be almost at the peak. I'll have get in the attic and take a look.

The hearth that is there has a TV on it now

 

[webby3650]

Can you re-line the chimney thats in place?

 

[begreen]

I know some people use the silicone flashings with success, but I often find them leaking. In addition to the risk of leaking, they offer NO support for the chimney like a metal flashing offers.
Anytime we do a metal roof install we use this one from ICC. It offers a permanent seal, it installs similar to a shingle type flashing, by tucking under the metal on the top side.

Here is the flashing to use: (broken link removed to http://www.icc-rsf.com/main.php?t=chem_produits&i=95&l=en)

Good advice. Do you have any roof shots of an install?

 

[webby3650]

Good advice. Do you have any roof shots of an install?

No, I usually take pics of the stove, but never thought to take a pic of the chimney.
I do a few a month through metal, I'll get a pic next time.

 

[Bret Chase]

flashing a metal chimney through a metal roof (screwdown or standing seam) isn't that big of a deal... if the hole stays in the flat and doesn't go through a rib. If it's a standing seam roof is is generally better to use the silicone boot and figure out a different way to secure the top of the chimney, as a SSR is only restrained at the bottom, and grows toward the peak as it heats up. With a screwdown it is also generally easier to use the silicone boot... though I have done a couple with a shingle type boot, but it requires cutting the panel....

if your hole transitions a seam in a SSR..... it becomes an ugly, ugly nightmare... the worst one I had to do involved 2 12" metalbestos chimneys that were less than 2' apart.... it took me almost 2 days to get it tight...

 

[charly]

If you're not sure, it would be wise to hire a professional so you don't damage the roofing. It is tricky to get the hole in the right spot.

When I went through my corrugated metal roof, I bought a stove pipe laser level that fits inside the top of the stove pipe or your wood stove and projects a laser dot right at the center point on the roof or what ever you are going through.. Was dead nuts on..scribed a circle after marking the dot and it was dead on plumb. I wound up using the silicone boot flashing kit..So far no leaks...

 

[eclecticcottage]

Just watching...we are thinking of doing a standing seam roof eventually, and we'll need to deal with this then.

 

[begreen]

Finally found a shot of the ICC flashing. I knew I had it sitting somewhere in my desktop junk.This is at the ridge, but the bottom detail is good. The storm collar has not been installed yet. Note that the sealant is only under the side flanges. The bottom is left unsealed for drainage.

 

[chimneylinerjames]

I would see what it would take to line the brick chimney. If its not in use, I would try to use the chimney that's already there. Just install a liner with insulation and your set.

 

[Bret Chase]

Finally found a shot of the ICC flashing. I knew I had it sitting somewhere in my desktop junk.This is at the ridge, but the bottom detail is good. The storm collar has not been installed yet. Note that the sealant is only under the side flanges. The bottom is left unsealed for drainage.

View attachment 92111

the bottom detail isn't great.... is that a foam closure on the bottom, or was the metal cut to fit?

 

[begreen]

I think he wants to get the stove more centrally located with a taller, straight up flue. The brick chimney is pretty short. Add a couple 90º turns in the smoke path and it is going to draw poorly.

 

[webby3650]

the bottom detail isn't great.... is that a foam closure on the bottom, or was the metal cut to fit?

It's cut to fit. I seal the bottom edge though. The customer can see daylight and they don't like it.
And I don't think there would really be any drainage allowed due to the size of the hole only inches away from the tail of the flashing. On a shingles roof it makes good sense, but here, I would rather seal it.

 

[Bret Chase]

It's cut to fit. I seal the bottom edge though. The customer can see daylight and they don't like it.
And I don't think there would really be any drainage allowed due to the size of the hole only inches away from the tail of the flashing. On a shingles roof it makes good sense, but here, I would rather seal it.

I seal it when I install them in a metal roof... I don't care what the customer "wants"... They never seem to like the "I told you so..." I don't want the callback for the chimney leaking due to wind driven rain, or the ice damn that *always* happens just down hill of the chimney...

 

[charly]

Finally found a shot of the ICC flashing. I knew I had it sitting somewhere in my desktop junk.This is at the ridge, but the bottom detail is good. The storm collar has not been installed yet. Note that the sealant is only under the side flanges. The bottom is left unsealed for drainage.

View attachment 92111

That's great if you can tuck the top under the ridge cap,, but that not always the case.

 

[Lumber-Jack]

Finally found a shot of the ICC flashing. I knew I had it sitting somewhere in my desktop junk.This is at the ridge, but the bottom detail is good. The storm collar has not been installed yet. Note that the sealant is only under the side flanges. The bottom is left unsealed for drainage.

View attachment 92111

My roof install was very much like this except the chimney came out a little lower down from the ridge cap. All you have to do is cut another piece of the same type of metal roofing and install it so the lower part over-laps the chimney flashing and the top goes under the ridge. Done!