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TOPIC: Flashing

dormer flashing

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could you reccommend a detail for flashing a galvalume roof panel at the side wall and front wall of a penetrating shed dormer. Problem: when installing the front wall flashing it runs atop the galvalume corrigations, and when side wall piece is run down dormer wall it is in between the corrigations, hence below the apron flashing at front wall when it should run over the flashing at this intersection. solution? all three pieces of flashing, 2- side walls and 1- front wall may be a continuous 90 degree angle bend. i can not use step flashing. is there a drawing detail for this? thanks.
Guest User

2/27/2008
Pete, If you will go click at the bottom where it says view more categories and and then go to DIY Do it Yourself and then on that page go to dormer flashing there are some drawings and also several replies. The two side wall flashings extend past the corner and over your front wall flashing. We make our sidewall flashings like a box trim with a foot that turns out over the panel. If the rib is close to the wall then our sidewall trim will go over it. If it is a ways away, we cut off the panel even with the wall. We make the box trim so the two sides match, if it is five inches on one side we make the other side the same. On the side with the cut off panel, we mark where the downleg of our trim hits the roof. We have already made a L shaped piece of metal the same height as our ribs. We put down a quality sealant inside of our marks and screw down the L shaped metal with the part that goes down on the panel turned towards the wall. We then put our box trim over that. The L shaped metal holds the box trim up at the outside, the screws are under the trim and do not show. If you are going to have to run a wide piece of trim then instead of making the inside metal L shaped make it U shaped and it holds your box trim up and flat on the inside and outside. The box trim---make a piece that comes down the wall say 2 inches, turns out away from the wall however many inches you need--say 3 inches then it turns down the height of the ribs and then turns out over the panel. The trim piece is stair stepped and all of the bends are 90 degrees. Sorry for the long post. [email protected]
Guest User

2/27/2008
thanks. understood. don't appologize for the length of the post. you made a clear picture with it. the use of the "extra" U-channel, or L was amissing element i would have never thought of as a carpenter. this is my first attempt at a metal roof, having completed the installation except for the dormer flashings, i would have liked to have found this site sooner- but i was reassured my instincs were right on after reading many posts here. i had put two layers of #15 felt down without realizing how beneficial it really is. i was just following basic carpentry sense. i would haave planed the overhangs at the eaves better, so there would be no need for trimming any panels for symetry. overall i like the material, and the roof on the pole barn planned for next summer will be a chinch-- no dormers!!
Guest User

2/28/2008
Thanks. Good luck. Todd Miller
Todd Miller
Isaiah Industries, Inc.

3/1/2008