Advertisement
If you have a new account but are having problems posting or verifying your account, please email us on hello@boards.ie for help. Thanks :)
Hello all! Please ensure that you are posting a new thread or question in the appropriate forum. The Feedback forum is overwhelmed with questions that are having to be moved elsewhere. If you need help to verify your account contact hello@boards.ie

Insulation recommendation for filling suspended floor

Options
  • 16-12-2023 3:11pm
    #1
    starstreamer8
    Registered Users Posts: 57 ✭✭


    I'm going to be doing some renovations and energy upgrades to a 1960s/70s house and looking for some advice / opinions

    1. I will be filling and insulating the ground floor which has suspended floors before putting UFH in. The cavity is plenty deep so was thinking 200mm PIR insulation but a builder said 150mm is fine and 200mm would be overkill. Will be putting UFH and 18 or 20mm engineered wood on top so really want good insulation. What do you think?
    2. Does the wood go directly onto the screeded UFH or does it need an underlay? Also regarding the wood, I wanted a 20mm think plank e.g. https://woodfloorwarehouse.ie/190-natural-plank-oak-oiled so that it will stand up to lots of sanding in the future but I'm worried it will be too insulating. Any thoughts? Should I stick to 18mm?
    3. Finally the house is in a high radon area so have asked the builder can he do a radon barrier and tape it up properly and also install a sump. Would builders in general be able to do this properly gas-tight or should I think about getting a specialist radon company to do the barrier before filling the floor?

    Last one! (for now!) Eventually I would love to get 200mm external insulation. What kind of overhang from the roof would I need for that? And if I don't have enough overhang, is it possible to extend it somehow at a reasonable cost?

    I thought the 200mm insulation external wrap insulation should go all the way to the ground but a builder mentioned that for the plinth the normal thing to do is just use a special water-resistant 60mm insulation. Makes it easier for gully access. Is that the usual practise?

    Grateful for any advice or opinions anyone has.



Advertisement