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Community and Q&A

Attach coping to membrane parapet…

monchgreen | Posted in General Questions on

I posted earlier about issues with coping metal on parapet wall – drips to outside, stains siding – and I appreciate comments received. Builder is working on a fix, but contrary to the opinion of a number of roofing professionals I’ve spoken to, he maintains that the coping material cannot be fastened/screwed on the interior side of the metal. First photo shows how coping is fastened on the outside. Second photo shows inside – no screws on this side. Third photo shows top of parapet. Anyone here have an opinion? Thanks!

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  1. Expert Member
    Akos | | #1

    You generally don't want to put screws on the membrane side as any ice build up can cause leaks through the screw holes. With such low parapets, I would agree with the builder, best keep all the fasteners on the other side.

    1. monchgreen | | #3

      Makes sense - hadn't thought of ice. Thanks!

  2. Expert Member

    This is near Seattle isn't it? Akos is right, but I'd temper the worry because of the mild climate. Poor detailing to have such low parapets in any climate though...

  3. monchgreen | | #4

    Yes - Olympia. Hoping to get coping angled to drain to the membrane. Some have suggested putting 1X2 under at outside edge, but not sure if that would fit with metal as is. Thanks!

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