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Window Drip Edge – Andersen 400

monkeyman9 | Posted in General Questions on

For Andersen 400 double hung, New Construction windows what is the proper way to have the drip edge.  Picture attached.

Is a drip edge only above the 1″ thick trim ok with just caulk between trim and top window ledge.  Or should there be a 2nd drip edge between the window and the PVC trim that is inset from the top?  This picture just shows caulk at this location.

The Andersen install guide shows drop edge right above the window, but it also does not show trim around the window.

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  1. Expert Member


    Are you using a rain screen?

    1. monkeyman9 | | #2

      This is with Zip Plywood and no rainscreen. LP Smartside.

      1. Expert Member
        MALCOLM TAYLOR | | #3


        Just the one head flashing (best practice is to include end dams). Unlike the photo you included, typically the window trim is thicker than the portion of the window frame that protrudes past the sheathing, so the caulking isn't as exposed.

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