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Cold roof cross ventilation

  • 06-04-2023 7:15pm
    Registered Users Posts: 5,982 ✭✭✭

    Got a new roof put on our extensions on a house we bought. Getting ready to insulate it now with 100mm PIR. Do I have to drill holes along the top of the joists to allow air to run through? How many holes and how big. I only have 150mm to play with in the majority of the joists. Worried about putting too many holes in and compromising the structure.