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Attic Foam insulation

  • 23-03-2021 2:29am
    Registered Users Posts: 3,303 ✭✭✭

    I'm not sure if this is the correct forum for this question but I'm looking to have my attic insulated.
    I've had some quotes to have it foam insulated which seemed like an interesting option.

    I did however speak to someone that suggested that if I'm not intending to ever convert my attic then it's a waste of time and that I should stick to the more traditional rock wool method., which I had done approximately 5 years ago.

    The pitch in the roof is very low so a full conversion is out of the question but I would however like to fully deck out the floor with one quote including this and to also.

    Coat the rear of the plaster board ceiling with 60mm open cell polyurethane spray foam insulation. Turn the old plasterboard ceiling into a new insulated plasterboard which will perform thermally and also limit moisture. Top off the spray foam system with cellulose flush with the joists.

    Any thoughts are greatly appreciated.


  • Registered Users Posts: 3,553 ✭✭✭horse7

    It's a great job better than the roll out rock wool or fiberglass stuff, get the cellular foam and leave air gap.

  • Registered Users Posts: 321 ✭✭Biker1

    Cheapest option is to have 350mm of mineral wool covering the entire area of the attic. Ensure your attic hatch is insulated and draught stripped. If you need a floor for some storage you could purchase props to raise the floor above the insulation level. Some hardware stores supply them. Spray foam does not act as a vapour barrier and while it may help with airtightness it is not an airtight product and is rarely installed as per the certification.