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Community and Q&A

Flat residential roof?

KrisCurrie | Posted in Energy Efficiency and Durability on

Residential architecture has been leaning towards flat roofs, from what I’ve seen they always leak!! What is the best way to insulate, and protect from ice & water breaching the asphalt torch down?
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  1. GBA Editor
    Martin Holladay | | #1

    Start by reading this article: Insulating Low-Slope Residential Roofs.

    After you read the article, you can post any follow-up questions here.

  2. Expert Member
    ARMANDO COBO | | #2

    Any roof leaks if it is not build right, flat or pitch. I've been designing modern and pueblo style buildings for decades, and none leak! Most box stores and commercial buildings are designed with flat roofs. To say flat roofs leak is a myth and/or lack of know how.

  3. user-2310254 | | #3


    The best way to ensure your low-slope roof does not leak is to hire a firm that specializes in installing low-slope roofs. My residential community has a fair number of these assemblies, and many of them leak. It is my understanding that the roofing contractors on these projects did not have much experience with this type of installation. So they were learning as they worked.

  4. Expert Member

    Climate dictates which building assemblies work and which carry risk. Armando designs beautiful, regionally appropriate houses in a dry climate. Here in the PNW commercial and large scale residential buildings frequently use flat roofs and they at some point invariably leak. The risk depends both on where you build and how.

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