Flashing for class A chimney through peak of roof?

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ericj

New Member
Oct 9, 2010
69
Iowa
My class 6 inch class A chimney is directly under the peak of the roof. The exit will be directly between two rafters with no support beam in the way. I could offset with a few elbows, but I'm wondering if the easier choice isn't straight up. Can anyone link to flashing for use on the peak? Thanks for your help.
 
Not that it CAN'T be done (we were faced with the same situation in our install, based on where the stove was intended to live), and I like the idea of the part that "tribe683" referenced.

My questions to the Town Inspector and the Installer (a professional outfit that does this sort of install all the time) about the peak, were answered with concerns about the integrity of the "stringer" (is that what you call that peak board? I'm not a carpenter), and the roof itself. Nobody wanted to lean towards altering the structural integrity, and recommended that slight bend section in the attic. the straighter, the better, when it comes to piping, and yet, the slight bend in the attic is not a big deal. It's not like doing a 90º Angle out the SIDE of the house! There are folks in here who will take exception to the aspersions they think I'm casting on their setup, because THEY have 90º Angles on their system, (and they look fine,.........I've seen the pictures in here); but I'm not intentionally going after them. If they are forced to do that, and if it works for them, ......great.......but the slight angle needed for the attic, to avoid the peak, will give you less trouble, (imho) than more extreme angles, with regard to creosote build up.

The only question was, which side of the peak to put the pipe. I preferred the front, facing the street, (some of course, prefer the back), just because I'm proud of the fact that we want to use wood heat, and be as free from foreign oil as we can. I wanted my neighbors to know that, and perhaps plant a seed in THEIR minds, about the ways they can be energy "green" and less dependent.

So, based on the best advice around, I didn't go thru the "stringer."

-Soupy1957
 
There will be no issue with strength if you use
standard framing techniques to box in the opening.
The ridge beam will not be compromised.
Think of it as putting in a skylight thru an existing roof
or a stairway thru a deck (floor). It's done ALL the time.
If your building inspector has a problem with it, you may
have a blueprint & to get an architect to sign off on it,
or you can bring him a standard carpentry & framing
textbook (they ARE available at bookstores) to show him
the framing specs....
A straight chimney drafts better & is easier to brush clean.
 
I ran into the same situation when I installed the F500 4 years ago. damn chimney ended smack dab at the peak. They make a peak flashing which had the 6-12 angle on both sides. I have a ridge vent so there was not a board in the middle. it was very easy and self explanatory to install.
 
Well, there ya go bubba........straight from the mouth of a Professional Installer. Sounds like it's do-able, with very little risk. I wish OUR "Professional" Installer would have suggested that. It might LOOK a bit more uniform, and "I" could have avoided the bend, even if it ISN'T a dramatic one (just because a "straight shot" is better than a bend, in terms of potential compromise over time). I don't know that I'm at any really greater risk for burn thru, or creosote build up with the slight angle in our piping, than a straight shot, but I HAVE heard that ANY angles can attract build up somewhat faster than straight piping. What that translates into, in terms of years, I dunno. Perhaps that means that my piping system might last 20 years, where a "straight shot" piping system might last 30 years? I haven't got a clue.

I CAN say that I had a "Licensed" Chimney Sweep come out back in the early Autumn, and I asked him if he had any trouble or saw any "issues" with the slight bend in the attic. He said, "no problems......everything is fine." So I guess I'm "good to go" even if I DO have a bend in the attic.

Outside of the benefit of the "straight shot," for the pipe, in the end, you could go either way, it would seem, and your system will be fine. I guess it comes down to what "you" prefer.

-Soupy1957
 
A followup question, thank you tribe683 for the link, can I use the ICC peak flashing with Selkirk Supervent chimney? I understand that the two chimneys aren't combineable, but the flashing is just a piece of metal with a hole. As long as the hole is appropriate for the Supervent I should be fine, right? The Supervent is 8.25 outside diameter, is this comparable to the ICC? Anyone know this offhand. Thanks again for the feedback. A lot of you have second career possibilities in chimney customer support!
 
Here is a link for the specs on the Excel Chimney.

http://www.icc-rsf.com/main.php?t=chem_produits&i=2&l=e&d=2&

Looking at the technical specifications in the lower box shows an outside diameter of 8.25" outside of bead on the pipe. To cap the flashing it comes with a Universal Storm Collar which is adjustable and you should be able to get it snug enough around your pipe (just confirm it does come with one if you do order the flashing). The installation instructions require you to caulk around the top of the storm collar anyway after it is installed, so I really think it would work for you. Here is a link to the storm collar.

http://www.icc-rsf.com/main.php?t=chem_produits&i=19&l=e&d=2&

Just asking, does Selkirk not have this type of flashing? If you do want to go with the Excel flashing, just let me know and I will get a quick measurement to confirm the 8.25" outside diameter. It won't be a problem.
 
Excel 6' Class A is 8-1/16 at the top (Male) & 8-1/8 at the bottom (Female) ends.
You'll have a small gap, between the cone & the chimney, but silicone will fill that.
The Excel flashings DO come with storm collars.
You hafta silicone the Class A twice. The flashing cone to the chimney & the storm collar to the chimney.
 

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