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does anyone have any information on r-foil bubble insulation for radiant slab installation. i have heard different views on double bubble. some people recommend it some dont. what should i recommend for future jobs.


  • Constantin
    Constantin Member Posts: 3,796
    I'd stay away from it...

    Bubble-foil manufacturers (and in particular their representatives) have been caught with inflating the effects of bubble-tarp, insultarp, or whatever they want to call it. Lofty initial claims of R-10, etc. have now been backpedaled to R1, if that.

    I'd go with extruded polystryene (XPS) a.k.a. Dow Blueboard. It has a known R-factor (R5/inch), is strong enough to walk on, and it doesn't absorb moisture. Whether you're looking for a mere thermal break or something thicker, my bet would be on XPS.

    Some alternatives like Rock Wool may work in applications where you can guarantee proper drainage, and rock wool isn't as susceptible to insect infestation as XPS allegedly can be (depend on where you live). However, you can get a borated version of XPS, which will keep the insects out of it for quite a while.
  • jerry scharf_2
    jerry scharf_2 Member Posts: 414
    recent studies have refuted manufacturer's claims


    There's not much right now that supports it's use, especially in slab situations. If you search the wall, there was thread about a Canadian study that was well done and clearly showed bubble stuff to be inferior to EPS or XPS foam.

This discussion has been closed.