Roof Support (ESR)

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New Member
Jan 9, 2024
Olympic Peninsula, WA
Hello. I just installed a wood stove and I'm trying to figure out whether I need to add something like this:

I've got a 48" section of chimney pipe that extends 24" down through a cathedral ceiling (in the support box), and then extends 24" up through the roof hole (cut 2" wider than the chimney pipe) with another 12" section of chimney pipe on top. Using the parts purchased as a "complete set" from the stove shop and following instructions, right now the only thing supporting that 5 feet of chimney pipe is the connection at the base of the support box and the little bit of "support" from the flashing collar. I am wondering if this is sufficient? Is it advisable to add something one of the roof braces I linked above?

Let me know if I can clarify any of that. Thanks in advance for any help.
Bracing is required for chimneys above a certain height, I believe it's 5'. However you may want to check if your chimney needs to be taller than it currently is, following the 3-2-10 rule as shown here
Roof Support (ESR)
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A bit tough to tell in this image but I am basically meeting the "3" and "2" part of that equation right at the mark (I did check). I think the "10" part is not so applicable here as it exits right near the peak. Attaching a picture for reference (caulk job kinda embarrassing, but I'm learning and it's definitely sealed if not excessive)

Any recommendations then based on seeing this pic? Should I add some type of brace?
Roof Support (ESR)
Ok yes I missed the part where you added another 12" section so your height is fine. I don't think this would need any additional bracing but someone more knowledgeable like bholler will probably come along to confirm that.
That looks like about 3' of chimney. It doesn't need a brace. No sense in adding any more holes in the roof than needed.
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Thanks for the feedback. Just to be clear though, I get that a full roof brace (requiring extra holes) is not required here (thanks for confirming) but my question was more if something like the collar brace that goes on at the roof exit (photo attached) is advisable since there is nothing supporting it there currently, therefore it is a full 5' worth of unbraced chimney (including 2' in the support box). Sorry if I'm just beating a dead horse at this point, just want have full confidence in what I've got going on. Appreciate all the replies.

Roof Support (ESR)
If snow starts to move down your roof, it won’t pick up much speed before it hits the chimney. I think you’ll be fine.
I would only worry if the snow gets over 3' high on the roof and that worry would be about the chimney getting blocked, Given the proximity to the water, not likely.
The support box should be enough to support the weight of the pipe above the box. The stove will share the job of supporting everything below the ceiling box. All the sections should be well seated and have three screws in them, with the lowest section sitting firmly on the stove or its adapter.
But those boxes are pretty strong and when I clean my chimney, I slide the telescoping pipe up off the stove a couple inches and while I’m pushing and pulling and getting pretty rough with the brush, all that force is being supported only by the ceiling support box. I have no concerns about that. Then I slide the pipe back down to the stove top and put the screws back in place.