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Two layers of felt under hot roof?

user-2423385 | Posted in Energy Efficiency and Durability on

I have a new roof in progress and am putting the insulation on top of the roof deck. I’m still waiting for my screws to arrive but I must waterproof for snow (the budget for screws is almost as much as the metal roof :)) and rain. I plan on putting 30lb felt over the 7/16 osb until my screws arrive and then add 6″ foam and then a layer of 1/2 OSB, then the metal roof. Do i need to remove the first layer of felt before adding the insulation or just leave it? Thanks

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  1. GBA Editor
    Martin Holladay | | #1

    There is no harm in having two layers of asphalt felt as you describe. Leave them and don't worry.

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