Foil bubble wrap insulation in cavity walls

Discussion in 'Eco Talk' started by Christopher Williams, Mar 10, 2021.

  1. Hi Everyone,

    I've been struggling to find a solution for years to no avail. On our estate, our houses were built in 2000 with cavity walls. As insulation, they used a thin bubble foil type insulation, about 1cm thick) as the cavity insulation pinned to the inner brickwork (something like Airtec foil). To me, this seems like wholely unsuitable cavity wall insulation. The house (and others on the estate) is forever cold.
    I've had people around to check on it and they have said that using blown wool and other types of insulation are unsuitable as due to the foil it couldn't be guaranteed and so they won't touch it.

    Two questions:
    1. Is a bubble foil such as the Airtec foil suitable for wall insulation? am I mad for wanting to fill the 10cm cavity?
    2. Has anybody seen this before and found any solutions?
    Screenshot 2021-03-10 141318.png
  2. just pumps

    just pumps Screwfix Select

    I have an uninsulated GRP boat and I`ve been looking around for insulation. I did find this and ordered a sample but it is expensive so I`m unsure whether to use it or not.
  3. Frutbunn

    Frutbunn Active Member

    Is it a Barratt built house by any chance? The insulation is probably Alreflex 2L2, and yes it is suitable for cavity insulation.
  4. Jimbo

    Jimbo Screwfix Select

    It might be cold because of a different problem, like the plasterboard not sealed top and bottom.
  5. fred812

    fred812 Active Member

    If that's the case what's the remedy?
  6. Red Star Boats

    Red Star Boats Active Member

    Seal it!
  7. Jimbo

    Jimbo Screwfix Select

  8. fred812

    fred812 Active Member

    Yes, but how to fix? In a previous property extension I had this problem (draught through electric back boxes) and I drilled holes at 6" centres along the top of the plasterboard wall and pumped a bit of expanding foam in, solved the problem but have always wondered if it was the right way. I had no access to the top of the plasterboard from above.
  9. rogerk101

    rogerk101 Screwfix Select

    You don't want that expanding foam to be in contact with the plastic of twin & earth cables. Sometimes the foam eats away at the plastic and some time in the future the cables may fail their insulation resistance tests.
  10. Jimbo

    Jimbo Screwfix Select

    @fred812 - that's basically the only way if you can't access the top of it (assuming that's where the leak is. A previous thread on here stated "Polyurethane expanding foam has no detrimental effects on pvc cable" as per response from a foam manufacturer.

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