Dormer ridge/roof plane intersection
Hi All,
I have a dilemma with the capping of a dormer ridge at its intersection with the plane of the main roof. I have made several, what I would consider, unsuccessful attempts to make the transition but the result has been cracking of the cap shingle at its top granular layer. My concern is that the performance of the cap shingle will be compromised as a result of the “cracks”. The dormer has an 18 in 12 pitch and the main roof has a 12 in 12 pitch. I am using IKO Cambridge LT laminated fiberglass shingles and capping with IKO Marathon AR 30 year fiberglass shingles doubled up with a 3/4″ offset at the butt ends and a 5-1/8″ exposure to the weather per the Manufacturer’s recommendation. I am cutting the cap shingles down the middle to facilitate following the “curve” at the transition and the weather is hot enough to soften the shingles to make them more pliable. Any suggestions would be greatly appreciated.
Salut,
Jeff
Replies
Yeah, that's a pretty tough bend for the caps transistioning from an 18/12 ridge onto a 12/12 plane.
I'd make sure (with I&WS or something sticky and formable) that the ridge/plane intersection is water tight and just use the caps as a cosmetic cover.
Cut the length of the caps down to where you just have enough room to nail them (an inch or so longer than the reveal). This will give you less to bend and reduce the cracking/tearing chances.
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Makes sense. Thanks seeyou, I will give it a shot.Jeff
Cut the shingles from the top to the top of the stick-tites. Lay and nail shingle, plastic cement cut. Next shingle, reduce the exposure of the color tab. Do same, plastic cement until done.