Building a new house and want a standing seam metal roof. Need help determining how is should be constructed. Material is 22 ga. Above the rafters, one roofing guy says radiant barrier OSB, 30# felt paper, metal. Another wants to put the metal on 1" x 3" lath. Nothing else. Any help/suggestions will be appreciated. Thanks in advance. Dick
Help with metal roof
May 23, 2008
10 Replies
I would go with the 30# felt. Temp changes with metal is going to give some sweating and you want your sheathing to stay dry. 30# felt is cheap anyway.
Thanks for the input. Would you have an opinion about a gap of some sort between the OSB and the metal to permit heat to be channeled up and out?
Check out the forum on:
formatting link
covers everything you want to know about metal roofing. Since there's many different types and applications, you really have to do your homework if you plan on going with metal.
With a gap between osb and metal you will get condensation. I used 30 # doubled with the metal mounted right on top.
Just about every standing seam roofing product I've seen uses concealed fasting clips that hold the panel 3/8-1/2" off the deck. =46rom what I've been reading (on the metal roof forums) is there should be at least a 1" air space under the panels.
What climate do you live in?
I understand that if one gets snow and the thermal and air envelope of the house is not done correctly and you have any valleys the snow will melt and and hang in the valleys. When conditions are correct it will freeze and push the roofing outward. This will wreck the roofing. If you desire the correct method of dealing with the thermal/air barrier (not the normal construction practices done today) let me know.
Andy Think and do Whole House Performance it is the right thing to do.
We'll be building on 19 acres just outside Ferris, TX. About 20 miles South of Dallas. Dick
What climate do you live in?
I understand that if one gets snow and the thermal and air envelope of the house is not done correctly and you have any valleys the snow will melt and and hang in the valleys. When conditions are correct it will freeze and push the roofing outward. This will wreck the roofing. If you desire the correct method of dealing with the thermal/air barrier (not the normal construction practices done today) let me know.
Andy Think and do Whole House Performance it is the right thing to do.
Unless I missed it I don't find any construction recommendations on
formatting link
Check out the forum on:
formatting link
covers everything you want to know about metal roofing. Since there's many different types and applications, you really have to do your homework if you plan on going with metal.
formatting link
formatting link
Join the Discussion
Have something to add? Share your thoughts — no account required.
Didn't find your answer?
Ask the community — no account required