Improving EPC. Floor Insulation

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    Improving EPC. Floor Insulation

    I am trying to improve the EPC of an old house,
    It has a cellar. I am thinking of applying Kingspan/Celotex between the joists beneath the ground floor.
    I have a choice of using either 25 mil Celotex or 50 mil Celotex, The 25 mil stuff is slightly cheaper than the 50 mil stuff.
    Will the difference in thicknesses make any difference to the EPC,
    All reptiles gratefully received.

    Only if the EPC assessor can be *rsed to take it into account.


      Check your current epc, always give you things that they look for and give you best results for your money


        In those circs I would use 100mm rockwool or glasswool or earthwool and a staple gun, which is about the same as 50mm celotex.

        If I had 100mm insulation in the loft I would use that, which would make the loft empty enough to qualify for a free upgrade to 250mm in many places.

        IMO 25mm is a silly idea as the cost saving is minimal and the benefit of 50mm is great. If you are going to do it, *do* it.

        If you are buying it take a look at places like Seconds and Co.

        If the house is a wreck I see no point in upgrading to less than a C due to the escalator we are on.

        Refer Mad Regulators to Arkell vs Pressdram.


          We insulated all the floors and some of the walls and the EPC surveyor said he couldn't take it into account for the EPC because he couldn't see it.
          Be sure to speak to your assessor before hand to make arrangements for him to see the insulation.


            Originally posted by slooky View Post
            We insulated all the floors and some of the walls and the EPC surveyor said he couldn't take it into account for the EPC because he couldn't see it.
            Be sure to speak to your assessor before hand to make arrangements for him to see the insulation.
            But even if he sees it, you still have the same problem in ten years time, when you need another EPC.


              Take pics or video on your phone before and after but make sure there are some identifying features so assessor can establish it is the property in question.

              Freedom at the point of zero............


                Insulating the floor well won't make a huge difference to your score, maybe 4 or 5 points if that.
                50mm kingspan has the insulating value of 150mm of rockwool.
                The first 100mm of rockwool does around 98% of the insulating (it is not linear).
                So you'll achieve as good a score (or almost) using 25mm kingspan, but if there is little cost difference, 50mm is usually easier to fit.
                Include the date in your pictures - not superimposed by the camera.


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