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TOPIC: Installation Process

Valleys on a dormer

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I am in the process of having a standing seam roof installed on our house. We have chosen 16" wide standing seam snap together panels. We have a 4:12 pitch with a dormer over a porch also at 4:12 pitch. The valley flashings have a 2" inverted v in the bottom of them. I have contacted the manufacturer several times for detailed information on how the two valley flashing should be lapped together on top of the dormer and sealed off. I can't get the manufacturer to offer any information. Today I was told that "there are several ways to do it and that it is the contractors responibility to install it properly". My ansewer to that was " I'm sure there are several way to do it but I am only interested in the right way". The work will be done by a contractor, not myself, but I do want to be aware of what a good installation should be. I'm very dissapointed that a company can engineer, manufacture, and sell a product, then put the responsibilty of making it work entirely on the contractor. Thanks for any input offered.
Guest User

9/14/2009
There are several ways to miter the two valley pieces together and seal them off to the roof. Your contractor may have a preferred method based on past experience. I have a preferred method as well. Unless your dormer runs to the eave of your roof, the more complex transition is where the valley stops. If you would like to e-mail me at [email protected], I will send you some pictures of my preferrred method. Again, it is not the only way to do it but it has worked well for me in the past.
Ken Buchinger
NCI Building Systems, Inc.

9/15/2009
E-mailed but no response, anybody else care to offer advise.
Guest User

9/17/2009
Bruce I have not seen your e-mail. I did get an e-mail from another gentleman with the saem issue and responded to him today. I will be happy to send you the same info and pictures if you send me an e-mail - [email protected]
Ken Buchinger
NCI Building Systems, Inc.

9/18/2009
Ken, The e-mail I sent you Came back on the 19 th as udeliverable, I am sending it again. Thanks.
Guest User

9/20/2009
I install waterproofing membrane "red rosin paper" to the decking...Tar paper sticks to the tin and is not recommended.... then in a valley there is a pan mine are "custom" ones are 41" wide "full sheet" almost with a V to stop wind driven rain and they go up each side about 18". to assure the wind don't get it in there.... most use a much smaller pan and that concerns me but they work because the manufacture recommends caulking them closed ....and at the bottom of the valley it needs to be 2 pieces or if one is slit and wedged into the pan you will need another piece or flat sheet under it to the bottom of the roof as it will get in the lil hole caulked or not it will tear open down the road .... If you take and cut across from the bottom of valley on the roofing another can be tucked under that one and the valley pan to pick up the water then there is a seam across 1 piece at the bottom of the valleys it is the best way to guarantee the water stays out...there is a few ways of doing the valleys soooo hope this helps there ya go good luck
Guest User

9/20/2009