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Kurtis Hord
Senior Member
Username: Kwhord

Post Number: 64
Registered: 10-2006
Posted on Thursday, July 10, 2008 - 07:33 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

This is quick and dirty, but let me know if you have any questions. The drive cleat is stainless because it is much more rigid than copper. This method keeps the apron from moving up.

Flashing spec
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Kurtis Hord
Senior Member
Username: Kwhord

Post Number: 63
Registered: 10-2006
Posted on Thursday, July 10, 2008 - 06:12 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

I'm just saying I would spec a continuous drive cleat to hold the appron. I see the potential for the whole assembly sliding upward toward the window, because the cleats only prevent downward movement. Your options are to double lock the cleats, or retain the apron by nailing the vertical part against the dormer. Neither of these are ideal.

A gusset is a soldered piece that fills in the triangle "gap" on the side of the apron.

Another little detail that I like to add is to clip the lower corners by about 3-4" and leave them un-hemmed. This is done to keep water running down the roof from hitting the hem and syphoning under from the side.

These are small details, and don't take that much more time to incorporate.
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Mark Woodhouse
New member
Username: Mrwoodhouse

Post Number: 8
Registered: 04-2008
Posted on Thursday, July 10, 2008 - 03:03 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Thanks guys. Ron, reason apron is long (6 inches) is in order to cover nails by 1.5 inches. Reason nails are so low is because I don't have anything to nail into for last couple inches flush with the face of the dormer. Kurtis, with 20oz copper and cleats every other slate I'd be surprised if wind could pick up, but maybe I'm underestimating. Are the hem and cleats enough to break the siphon effect? What is a gusset? The apron extends up the sides the same length as up the front of the dormer. I was planning to wrap the step flashing around the apron. Would you advise another method? Thanks.
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ron kugel
Senior Member
Username: Slateworks

Post Number: 56
Registered: 09-2006
Posted on Monday, July 07, 2008 - 09:56 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Hey Mark it looks good--you could of made the front edge of apron extend down the slate just 3" so it would have been at the same exposure as slate--but it is not a big deal--drill and nail about 1.5" from edge of cleat for first hole ,would also add one more nail 1 or 2 inches above the first one--if you can the kick down or cant is a good idea on the front edge of apron--a continuous cleat was mentioned it may help hold apron a little more secure--you can go to the home page and search under HOW TO : Installing copper snow apron and see example of long cleat--Can also view Traditional roofing no.6 issue that shows apron and cleat...but I think a cleat installed at every other butt joint would work just fine,especially with 20oz and a hemmed front edge.
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Kurtis Hord
Senior Member
Username: Kwhord

Post Number: 60
Registered: 10-2006
Posted on Monday, July 07, 2008 - 08:11 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Mark, I have a few suggestions:

There may be a problem with the cleats you are using. They only keep the apron from moving 1 direction: down. If the apron is ever pushed up by wind those cleats may not hold. If this were a smaller apron in front of a chimney it wouldn't be such an important detail. But you have a lot of surface area there and I think the potential for wind lift is pretty high. A continuous drive cleat would be the best way to secure this apron and keep your fasteners hidden. I don't have access to illustrator right now, but I'll post a diagram when I can.

Next, you are going to have to add a soldered gusset to the sides of that apron. It looks like it should extend higher but maybe it's just the way the picture is taken?

And finally, I would also add a small cant at the bottom of the apron to prevent syphoning.
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Tim Dittmar
Junior Member
Username: Tim_dittmar

Post Number: 11
Registered: 05-2008
Posted on Monday, July 07, 2008 - 12:59 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Mark- I anticipate serious electrolysis problems only where dissimilar metals are in contact and are often/frequently/always wet.. there are trace metals in slate(the color/s, etc.)- copper isn't impervious to these issues but more like resistant and steel/zinc less so- from reflashing a few times in my life, the damage seems to be primarily where compost elements and water linger- between the slates and the exposed side of flashings- providing for isolation of steel siding from copper step flashings is not a bad idea(per se) and perhaps a "drape of even heavier felt(30lb) between them would be great forethought- 30 lb in a shingle/flashing scenario creates problems
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Mark Woodhouse
New member
Username: Mrwoodhouse

Post Number: 7
Registered: 04-2008
Posted on Sunday, July 06, 2008 - 11:52 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Thanks Ron. I made the apron and did the hem as you said. Are the cleats I made in the pic right? I haven't nailed yet. What is the minimum distance up the cleat that I can nail? Is one or two inches OK? And just one nail or two and you said between the slates, so I still need to go through the underlying slate. Do I drill that? Thanks again.
Mark
Woodhouse garage 9


woodhouse garage 11

woodhouse garage 12
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ron kugel
Senior Member
Username: Slateworks

Post Number: 55
Registered: 09-2006
Posted on Friday, July 04, 2008 - 04:54 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Hi Mark - Just fold the metal one time all the way over so that it is twice as thick at the edge -we usually do a 1/2" to 3/4" hem- this helps stiffen the front edge--you can also leave this flat or give it a bend down against the slate-usually just the width of the hemmed edge--the cleats(straps) are nailed between the slates that will be under the apron flashing ,make them about a 1/2 to 3/4 of an inch longer than the front edge of apron flashing-I like to set the apron in place and mark where it meets the cleats-remove the apron flashing and use tongs to start the bend of the cleats-then reset apron than continue folding over the cleats with-tongs-hammer-and hands what ever works good for you-then some will solder the folded edge of cleats or you can leave them be- 2' apart ,it varies-Look on this site at some of the Traditional roofing articles and I think you will find some images and info that would help...also the others gave you good info about not nailing the step flashings to the sidewall - we make our steps 1" longer than needed and nail them above the top of the slate and on the outside corner (away from the vertical surface)-do not overdrive this nail -the head of nail should sit even with the top surface of slate ,if you overdrive it the bottom edge of flashing will lift off of the slate-also like to set the flashing in place to see how it fits then adjust it with some extra bending with your hands if needed,so it rest nice and flat against both surfaces.
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Mark Woodhouse
New member
Username: Mrwoodhouse

Post Number: 6
Registered: 04-2008
Posted on Friday, July 04, 2008 - 12:37 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Thanks. You guys are awesome. Kurtis, I am planning to finish the dormer with cedar clapboard siding. Ron, I like the sound of your hem finish for the dormer apron, but am unfamiliar with the terms. By a double fold, does that mean fold the length of the front of the apron twice? How wide is each fold? And I like the strap(s) idea. So is there one strap that runs the length of the front of the apron and fits in the double fold? How do you attach the strap? Tim, is the felt on the step flashing only necessary for steel siding, so wouldn't need it if using wood siding? Thanks everyone for the great assistance.
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Kurtis Hord
Senior Member
Username: Kwhord

Post Number: 59
Registered: 10-2006
Posted on Thursday, July 03, 2008 - 05:30 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

YES! Do not nail to the dormer wall. My step pieces are headlap+exposure in length and 4"X4" on the bend. I slide them up just enough to nail right above the course, and I put 1 nail in the top-left corner. Sometimes it helps to bend the corner down a little so the piece will lay flat.
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Tim Dittmar
New member
Username: Tim_dittmar

Post Number: 10
Registered: 05-2008
Posted on Thursday, July 03, 2008 - 11:31 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Mark- it helps the future of this roof to not nail the flashings to vertical surfaces or anywhere else where the nails can't easily be removed for a reflashing procedure- the step-flashings should be over-sized enough to make nailing through slates unnecessary- the minimum would be an exposure plus a headlap in length but that wouldn't allow a simple nailing to the roofdeck- oversizing somewhat the length and width makes it possible to nail flashings other than near the edge(rather the upper-outboard quadrant) to springload them down and avoid nailing behind the siding-(theoretically,anyhow)- you might have to bend the steps out of 90 a little to get them to hug the vert. surfaces. 15 lb felt strips on top of flashings and under the slates(but not visible) can electrically isolate the metal and extend performance times- galv. steel even more so
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Kurtis Hord
Senior Member
Username: Kwhord

Post Number: 58
Registered: 10-2006
Posted on Wednesday, July 02, 2008 - 07:31 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

What are you finishing the dormer with?

If I have an area like that where I'm going to use a really wide apron, I usually solder a continuous cleat onto the base flashing and then lock the counter flashing to that. If you're using lap siding, it will act as your counter flashing so you won't need copper counter flashing.

Is it too late to consider slating the dormer?
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ron kugel
Senior Member
Username: Slateworks

Post Number: 54
Registered: 09-2006
Posted on Wednesday, July 02, 2008 - 05:19 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Yes= Continue with the last row of slate you show in the pic -then install the next row and cut to fit around and in front of dormer- the front flashing can be installed a few different ways - by running the 2 rows of slate your headlap is taken care of so you will have to determine how wide you want your front flashing(onto the slate)at least 3"--add 3 to 4 inches for the face of the dormer - add 3 to 4 inches to extend past each side of the dormer -Bend flashing at proper angle - give the front edge a 1/2" to 3/4" kick down,just enough to stiffen edge that will rest tight to the slate--or you can hem the front edge(double fold )--then either install straps slightly longer than the front of flashing that would be folded over to hold down edge of flashing - or you can drill holes thru metal & slate and use 2" copper nails to hold down front flashing(do not overdrive-set flush so you do not dimple copper) -or the flashing may not need anything for the front edge to hold it down, if the bend is good and it is not to wide-have to decide once you install it--once the front flashing is cut to fit and installed --then you can fit the step flashings on the corners by either extending them past the front edge of dormer to match the front edge of front flashing and folding them over (once the siding is done on the dormer - or you can fit and hem them to form a tight corner and solder the joints..hope this helps--someone may be able to load a few pics -or check out old postings may be a few pics that would help.
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Mark Woodhouse
New member
Username: Mrwoodhouse

Post Number: 5
Registered: 04-2008
Posted on Wednesday, July 02, 2008 - 12:48 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

I have 20oz copper 16 inches wide to flash this dormer and need some help. I have the slate roof bible and see how to step flash the sides, but what about the front and the corners. Do I treat just like a chimney?Woodhouse garage 7Woodhouse garage 8

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