Thanks for posting. Because of the ventilation beneath the decking, you should be fine with a direct to deck installation. Is there a vapor barrier behind the ceilings? It would not be a bad idea. As far as standing seam product selection ... drop me an email and I have a couple of articles I can send you that explain the things to look for / think about. todd@asktoddmiller.com
Todd Miller
2017-12-04 08:58:55.000000
Hello, I am building a home in western North Carolina. 3.5:12 on 14" TJI's (2x6 on overhangs and rakes). Right now, I have 5/8 plywood and Dupont synthetic underlayment. I plan on continuous ventilation under the decking from eave to ridgeline by boxing in the top cord of the TJI under the decking and will be insulating with dense packed cellulose below that.
I would like to do a standing seam roof. Would I need to do lathe strips with this setup or can I go direct on the decking?
Also, any advice on picking which standing seam style or product is more than welcome.
Thanks, Andrew
andrew herrington
2017-12-03 14:11:31.000000
Thanks for the reply!
Todd - the plan was to drywall the ceilings and use a latex paint. I will email you shortly about the SS. Thank you
Eric - the top cord of the TJI is 2" so I planned on using that to box out the vent channel. Thank you for the article!
andrew herrington
2017-12-05 13:51:04.000000
+1.
Direct deck works great here.
I would like to see about 2" of ventilation here if possible. A foil face foam (foil facing the back of the roof deck) would work great here to box out your vent space.
You do want something that is a class one vapor retarder here to prevent any dissolved moisture getting into the vent space.
http://www.finehomebuilding.com/pdf/021221068.pdf