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Community and Q&A

Metal roof ridge decking gap

eorr | Posted in General Questions on


I’m using Zip roof decking. My contractor put the panels on from the bottom up to the ridge. There is about a 6 inch gap at the ridge, which he covered with membrane. I realized after he put the metal on, he cut the membrane away at the top of the metal sheets. So there is about a 2 inch gap underneath the ridge cap.

Should I be concerned about condensation from the ridge cap dripping into my ceiling?

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  1. Expert Member


    That's how all vented roofs are built. You can't have a continuous ventilation channel with a roof underlayment covering the outlet.

    With a metal roof, any condensation will run down the underside of the cap and drop onto the panels well beyond the gap.

    1. eorr | | #2

      Thanks, I realized that was probably the case after I posted this.

      1. Expert Member
        MALCOLM TAYLOR | | #3


        One less worry!

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