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Community and Q&A

Sealing a door threshold

mikeferro | Posted in General Questions on

I am building a new home that utilizes Intus windows and doors in my quest to achieve maximum energy efficiency.

When planning the project I took a painstaking amount of time to detail the window installation and was pleased with the result from my builder. However, I overlooked the doors and standard metal flashing was used during the installation. During the initial blower door test, we found the door sill was leaking a considerable amount of air under the metal flashing and warranted better sealing.

My initial thought was to cut back the gasket material and metal flashing under the door sill and try to seal the door sill over the metal flashing to the concrete foundation wall using Fentrim. However, the Fentrim simply doesn’t stick well enough to the concrete to give me confidence that this is a good long-term solution.

I’m hoping not to remove the 200lb Intus door and wondering if the GBA community has a creative solution?

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  1. GBA Editor
    Martin Holladay | | #1

    The copper is a thermal bridge. If I were you, I would probably cut the copper flashing back tight to the door threshold, and then seal the seam(s) with either (a) Siga Wigluv tape, which sticks to concrete, or (b) caulk.

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