metal roof const. over present flat roof

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metal roof const. over present flat roof

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I am considering constructing a metal roof structure over a present single ply membrane flat roof on a 5 unit townhouse apt. bldg. 30x85 ft. long. Shed roof style so one pitch (not gable) with 2x6 rafters and 2x4 purlins. I will open the single ply membrane but leave it in place. The reason for all this is I have soft decking under the membrane which problem needs to be solved and it's time for a new roof. I will have lots of ventilation in the new space above the present roof and under the new construction. My question is how to avoid the condensation issue under the new metal which I think I already have under the membrane but am hoping will be alleviated by opening the areas of problem. What advice do you have for me? Thanks.
Guest User
2015-04-24 18:51:09.000000
If the membrane is intact, the moisture issue with remain at the membrane level. I would seriously think about adding some insulation to the roof deck (membrane level) so as to move the roof structure and sheathing into the warm wall and stave off the condensation.
Eric Novotny
2015-04-25 16:38:01.000000