I’ll be meeting soon with a couple copper roofing contractors, to see which might be best to roof an eyebrow dormer.
The entire rest of the roof will be done in Iko Chateau architectural shingles, and just the eyebrow piece will be coppered.
I was hoping to get some thoughts from you roofing pros about what is best for prepping the deck for the copper, and how to handle the flashing at the shingle/copper interface.
The attached .pdf print shows a birdseye view of the roof, with the porch dormer evident. The large radius is 20′ R, and the small fillet transitions at the bottom corners are 9′ R each.
The line around the edge of the dormer projection is where the 4-1/2 pitch roof plane intersects the dormer roof.
BTW, this is all unheated below. It’s over a screened porch.
This is an aesthetic question. The pitched shingled roof flanking both sides will have, at its fascia edge, dark green painted metal drip edge. Would you change to copper drip edge, right at the fillet transition, and carry the copper up and over, then change back? I am presuming we can make the copper to the same “reveal” shape as the painted metal.
What gage or weight copper sheet is recommended?
Can this be done in a small standing seam arrangement, the seams running up and over the arch?
Will the curved valleys be difficult to do in copper?
How much of a holdback off the valley center should the shingles be laid?
Will two thicknesses of 3/8 CDX be an OK deck substrate? Will we be able to flex the 3/8 to the frame?
Ice and watershield the whole thing? Anything else underneath?
Edited 2/23/2005 10:26 am ET by Gene Davis
Replies
Would you change to copper drip edge, right at the fillet transition, and carry the copper up and over, then change back? I am presuming we can make the copper to the same "reveal" shape as the painted metal.
Yes.
What gage or weight copper sheet is recommended?
16 oz.
Can this be done in a small standing seam arrangement, the seams running up and over the arch?
I don't see a way to do it in standing seam that won't make the water try to run over the seams. Flat seam would be more feasible.
Will the curved valleys be difficult to do in copper?
No more difficult than any other metal. It has to be done in a series of small pieces.
How much of a holdback off the valley center should the shingles be laid?
That's a cosmetics issue in this case. I normally like to show 3" of valley from the center.
Will two thicknesses of 3/8 CDX be an OK deck substrate?
Yes.
Will we be able to flex the 3/8 to the frame?
Don't know - looks like it should work.
Ice and watershield the whole thing?
Good idea - then use Rosin paper between the I&WS and the cu so the I&WS doesn't melt and run thru the seams when its being soldered.
Like the Tucson, I shall rise again from the ashes.
Thanks for the response. Very helpful information.
The attached pic shows how I was thinking the seams would go, if they were raised seams. Those lines are 12 inches apart, so you can get an idea of the area involved.
We're doing this project from plans done for a home already built. The original has a 100% standing seam steel roof, and the eyebrow dormer has its panels run this way over the eyebrow.
Still look OK to you?
If we flat-seamed it, and run the strips the other way, is it an easier job?
Given its size, about how long do you think this thing should take to install?
I think it's a bad idea to run the standing seams that way with the shingle roof above dumping on it. If it were at the top - no problem.
Forming a curved standing seam roof takes special tools and skills many roofers don't have. The flat seam roof doesn't take any special tools, but the skill level is pretty high.
Timewise, standing seam would take me about a day to layout and fabricate and probably a day and a half to install. Flat seam would take about half the time and I'd be more comfortable about it not leaking.
If you decide to go with standing seam, make sure the seams are double rolled - not single and definately no applied caps. Good luck.Like the Tucson, I shall rise again from the ashes.
Thanks again.
Absolutely no reason at all to go standing seam, everything now considered.
So, a flat-seamed arrangement would go front to back, now? Right? Perpendicular to the up-and-over lines I drew?
Are we screwing down with concealed clips hooked to each seam?
Seam-to-seam width, or strip width?
I just want to be as fully informed as I can before engaging one of these local guys.
Edited 2/24/2005 8:58 am ET by Gene Davis
Here ya go:
http://www.copper.org/applications/architecture/arch_dhb/roofing/flat_seam_roofing.html
I don't like the drip edge detail shown. I use a more standard shingle style ( I think it's "d-style" ) drip which conforms to the curve easier by slitting the verticle face and letting it overlap.
I'd run the pans front to back, coming up from the valley to the top on each side, but they could be run the other direction as well.Like the Tucson, I shall rise again from the ashes.
Thanks again.
Wow, that server that copper.org has is a slow one!
You wouldn't want to take a short Adirondack vacation this summer, would you? Sort of a working trip?
You wouldn't want to take a short Adirondack vacation this summer, would you? Sort of a working trip?Maybe.Like the Tucson, I shall rise again from the ashes.