Help with new roof, chimney reinstall

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Drat

New Member
Aug 19, 2022
2
Northern MN
Hey all, brand new to the forum and I really like what I see here so far. I'm guessing you guys can answer my questions in a heartbeat.

I have a seasonal cabin in Northern MN. It has a cathedral ceiling decked with 2X6 tongue and groove. Previously, there was no insulation in the roof, and we heat with wood (Lopi Endeavor). As you can imagine, we have experienced some mighty ice dams, but in the past we've only been up there sporadically in the winter so we just dealt with it. Last winter we spent quite a bit more time up there and we measured over 10 feet of snow on the deck so it was a pretty unmanageable situation. This summer we tore off the metal roof, stacked 5 1/2" of foam board on top of the tongue and groove, laid 1X4's running up the roof pitch 16" on center to form an air gap and finished with plywood decking. I'm looking forward to putting new standing seam metal on in late September.

I'm currently planning the reinstallation of the wood stove chimney. The chimney is 6" ID Selkirk Metalbestos SS2. It was previously installed with the universal roof support kit, an angled bracket with two metal plates that screw into the roof deck. This looks like it. The transition chimney piece passed through the square hole in the ceiling with the required clearance and joined the single wall pipe to the stove. The square hole was hidden with a circular metal ceiling plate. I can't find an example online, but it's just like it sounds. A circular black metal plate attached to the cathedral ceiling to hide the big ugly square hole. There was no support box, as the chimney support was being provided by the angled bracket.

A couple of questions:
1.) Ceiling support box? Do I need one or can I simply reinstall using the universal support bracket on the new roof deck and the circular ceiling plate? What are the pros and cons of adding a support box? (I am planning to bring a section of class A sufficient to extend the length of the pipe through the roof, because the roof assembly is now 8+ inches thicker than it used to be.)

2.) What type of flashing? The previous flashing was vented flashing with a storm collar, probably Selkirk brand, knowing the previous owner. It was mangled horribly in the demolition. We never had any noticeable leaks, but as I mentioned, it's a seasonal use property, so maybe we did have leaks in a driving rain but just never when we happened to be there. I would much prefer to go unvented on the flashing to keep bugs and critters out. There are LOTS of bugs and critters around. The guy I bought the stove from recommended the ICC EMFA-B-C metal roof flashing with a thicker bottom edge that can be cut to work around the roof seams. Do I need Selkirk vented?

Any thoughts would be much appreciated. I'm trying really hard to get all my ducks in a row before I head up to install the roof, because the cabin is a long way from anywhere that might have pieces and parts I might need.
 

begreen

Mooderator
Staff member
Nov 18, 2005
96,491
South Puget Sound, WA
It's ok to use the angled roof bracket as long as it is in good condition and there is a good solid surface to anchor to. Likewise, it's ok to use the ICC Excel flashing as long as it is for the same diameter chimney. It's also important will be to make sure that the chimney pipe clearance of 2" is honored or exceeded.
 

Drat

New Member
Aug 19, 2022
2
Northern MN
Thanks for the quick reply. Is there any insulation value to using a support box as opposed to just the decorative ring to cover the square opening?
 

begreen

Mooderator
Staff member
Nov 18, 2005
96,491
South Puget Sound, WA
That's a reasonable question. I think this will vary depending on the chimney pipe manufacturer. Some might permit their insulation to be used against the chimney pipe while others do not.
 

switepine

New Member
Feb 28, 2022
53
heJinx22
Hey all, brand new to the forum and I really like what I see here so far. I'm guessing you guys can answer my questions in a heartbeat.

I have a seasonal cabin in Northern MN. It has a cathedral ceiling decked with 2X6 tongue and groove. Previously, there was no insulation in the roof, and we heat with wood (Lopi Endeavor). As you can imagine, we have experienced some mighty ice dams, but in the past we've only been up there sporadically in the winter so we just dealt with it. Last winter we spent quite a bit more time up there and we measured over 10 feet of snow on the deck so it was a pretty unmanageable situation. This summer we tore off the metal roof, stacked 5 1/2" of foam board on top of the tongue and groove, laid 1X4's running up the roof pitch 16" on center to form an air gap and finished with plywood decking. I'm looking forward to putting new standing seam metal on in late September.

I'm currently planning the reinstallation of the wood stove chimney. The chimney is 6" ID Selkirk Metalbestos SS2. It was previously installed with the universal roof support kit, an angled bracket with two metal plates that screw into the roof deck. This looks like it. The transition chimney piece passed through the square hole in the ceiling with the required clearance and joined the single wall pipe to the stove. The square hole was hidden with a circular metal ceiling plate. I can't find an example online, but it's just like it sounds. A circular black metal plate attached to the cathedral ceiling to hide the big ugly square hole. There was no support box, as the chimney support was being provided by the angled bracket.

A couple of questions:
1.) Ceiling support box? Do I need one or can I simply reinstall using the universal support bracket on the new roof deck and the circular ceiling plate? What are the pros and cons of adding a support box? (I am planning to bring a section of class A sufficient to extend the length of the pipe through the roof, because the roof assembly is now 8+ inches thicker than it used to be.)

2.) What type of flashing? The previous flashing was vented flashing with a storm collar, probably Selkirk brand, knowing the previous owner. It was mangled horribly in the demolition. We never had any noticeable leaks, but as I mentioned, it's a seasonal use property, so maybe we did have leaks in a driving rain but just never when we happened to be there. I would much prefer to go unvented on the flashing to keep bugs and critters out. There are LOTS of bugs and critters around. The guy I bought the stove from recommended the ICC EMFA-B-C metal roof flashing with a thicker bottom edge that can be cut to work around the roof seams. Do I need Selkirk vented?

Any thoughts would be much appreciated. I'm trying really hard to get all my ducks in a row before I head up to install the roof, because the cabin is a long way from anywhere that might have pieces and parts I might need.