This topic has been closed by the administrator. Comments are no longer accepted.
I am putting a galvalume sealed standing seam with Kynar finish roof on a 50 yo 1 1/2 per 12 slope roof. Some of the roof is shingles on tar paper and 3/4" dense planks over cathedral ceiling with poor vapor barrier and 6" rock wool insulation. The rest of the roof is the same shingles on planks over unvented attic with good insulation. The location is East Tennessee at about 1,000' elevation. I am putting 30lb felt and rosin paper under the metal over the shingles. Would you recommend planks over the shingles for winter moisture ventilation of the cathedral section? What about the attic section? Should the attic be ventilated instead? That negates the summer moisture barrier effect of the sealed roof. Or does it?
Thanks for your help!
George
Or copy this URL:
https://www.metalroofing.com/spirit/comment/5841/find/
The building code is clear. You must ventilate and use a moisture barrier under the roof covering. Attics musyt be vented equally at the soffit and ridge to 1/150 and the vauted ceilings must have a minimum 1" vertical air space vented at the eaves and ridge. Also I do not beleive rosin paper qualififies as an apporved moisture barrier and in fact I would be suggesting a breathable membrane.
Sooner or later all that moisture and heat will work away at the lifespan of the entire roofing system without it.
5/2/2005
Or copy this URL: https://www.metalroofing.com/spirit/comment/5841/find/Dura-Loc Roofing Systems, Inc.
5/6/2005
Or copy this URL: https://www.metalroofing.com/spirit/comment/5842/find/