How to/Should I brace

[ToltingColtAcres]

My chimney is roughly 20-22ish feet. It comes out near the peak of my house, perhaps 2-3 shingles from the peak (~6/12 pitch), and extends about 2' above the peak (so about 3' give or take from the flashing collar through the roof.

I thought I would try to improve draft and experiment this year by adding another section of pipe, so I picked up another 3' section and installed it. Now I have about 5' extending above the peak.

The question: should I brace the pipe?

I picked up a roof brace kit, but according to the instructions I would need a roughly 45 degree angle and install roughly 2/3rds of the height above the pipe.

If I went up 2/3rds of the height, this would put me about 3.5", or about 1' above the peak (and perhaps 6" above the locking band). Since I'm so close to the peak at the roof line, I think I'd have maybe 2' of actual brace, assuming I put the brackets right at the roof peak. No way I'd get 45 degrees. More like 60.

Or, should I be okay to leave it unbraced?

Or, does someone have another suggestion?

 

[ToltingColtAcres]

a better view with the 3' section attached

 

[Heatsource]

best would be a stick built insulated chaise...

yes you should brace it, if 5' tall

(the pipe being crooked would drive me nuts)

 

[iron]

well, the brace, i assume, doesn't need to be perpendicular to the roof pitch or pipe. so, could you just move the base of your brace such that you keep the 45 degree angle + 2/3 of height per the attached image?

keep in mind, the capacity of the brace is affected by its length. also keep in mind that a brace at 60* compared to 45* sees a 40% load increase.

 

[begreen]

Yes, definitely add a roof brace. Here are the installation instructions for a brace from DuraVent. 60 degrees is their recommendation:

 

[ToltingColtAcres]

Thanks, I ran a brace from about 2' below the cap to as close to the peak as I could manage. Can't tell the exact angle, but, I guess its better than nothing

As for bring crooked, the house is 278 years old, so nothing here is straight or plumb I didn't install the chimney, and I never noticed it being crooked, I guess the extension makes it more obvious.

 

[bioman]

I built a chase around mine & it works good & looks good.

 

[realstihl]

I built a chase around mine & it works good & looks good.

No bigger than that one is, most of it could be pre-built on the ground.