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Community and Q&A

Using Ice and Water Shield Past Exposure Date

stolzberg | Posted in General Questions on

Long story short, my new metal roof project was supposed to be completed last summer, but the roofer sub made a mess of the project and our contractor halted work.  They had the entire roof covered in Grace ice and water shield in December and were going to find a new roofer to put on the metal roof with hidden fasteners as soon as they could, but it still hasn’t gone up yet.  I see the ice and water shield has a 90 day exposure limit, which we have just about reached.  What are the options after reaching the exposure limit: can the metal roof be put on over existing ice and water shield after 90 days?  Does the ice and water shield need to be torn off and replaced?  Can another layer be put on over it?

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  1. Expert Member
    DCcontrarian | | #1

    Put another layer on before you hit the limit.

  2. Expert Member


    And as that second layer is only there to protect the I&W against UV, it can be any cheap sheet underlayment.

  3. stolzberg | | #3

    Thanks for the feedback. Our contractor has suggested temporarily tarping the roof as we approach the limit; would that be sufficient or do you think another permanent layer before putting on roof.

    1. Expert Member
      MALCOLM TAYLOR | | #4

      Any cover within the 90 day limit for exposure stops the clock. I wouldn't be worried about it after that.

      Is it regular I&W or the HT? I'm not sure the regular version is approved for metal roofs.

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