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Cedar shingle siding installation over a window

user-7061227 | Posted in Green Building Techniques on

My builder insists that the shingles over a window and door should touch the flashing. The Maibec instructions insist that there be a 1/4″ gap between the siding and the flashing. I would appreciate any thoughts.

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  1. Expert Member
    Akos | | #1

    Your builder is wrong.

    There is always be a gap between the head flashing the the siding and the head flashing needs to be lapped by the WRB (it needs to go behind the house wrap). The head flashing should also be sloped to drain outside. The idea is to channel any water flowing down along the WRB from above the window out.

    With painted cedar, adding a spacer mat (ie Home Slicker) makes a big difference on the durability of the finish.

  2. user-7061227 | | #2

    I thought so.
    We used siga majvest
    We used Tyvek rain drain
    We taped the top of the head flashing to the majvest
    After all that I didn't want to fail at the siding stage.

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