Posting a message to the forum will remove the above advertisement
  1. This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn More.
  2. Checkout our Tilers Insurance area for awesome prices on Van Insurance and Public Liability Insurance for Wall and Floor Tilers

Discuss waterpoofing on concrete floors with underfloor heating in the Tiling Forum area at

  1. Raccus

    Raccus Active Member

    Situation is bathroom with shower cubicle. Off the shelf shower tray (stone resin?) 170 x 80cm. Two shower walls are in finish plaster on brick, 3rd wall will be glass onto tray base. Remaing side will be open with no door. Floor is concrete, with prowarm insulation boards (waterproof they say)+ loose wire underfloor heating. Floor and walls to be tiled.

    1 tanking for the 2 shower cubicle walls, membrane system or paint on?
    2 does the floor need tanking under tray, or if using membrane system in step above that goes down and rests on tray base, is that sufficient
    3 wasnt going to tile inder tray, or should that be done?
    4 the rest of floor, does this need tanking?
    5 if so, where should the tanking fit in, considering the concrete floor needs: insualtion boards, self levelling and loose wire UFH. Id guess tanking if needed goes on top of levelling compound then install UFH over this?
  2. Andystiletiling

    Andystiletiling Trusted Advisor Professional Tiler

    I would use a paint on tanking system on your walls, TM, Mapie, Webber, Ardex all make decent systems, better check your tile weight limits onto a skimmed wall as its only 20kg psqm. Its a normal shower tray then yeah...not a wetroom? If so fit tray onto a bed of tile adhesive, tank walls then tape the wall corners and down onto lip of tray with tape provided with the kit, no need to tank under tray or rest of the floor. The leveler goes over the ufh wires and insulation boards then floor tiles.
    • Like Like x 1
    • Agree Agree x 1
  3. Plan Tec Tiling

    Plan Tec Tiling Administrator Staff Member Trusted Advisor Professional Tiler JOTM Winner Top Contributor

    Wimborne, Dorset
    • Like Like x 1
  4. Raccus

    Raccus Active Member

    Ok thanks Andy and Plan Tec. Yes shower tray, not wetroom.
    As for tanking rest of floor, no it shouldnt need it, but have seen mention of 50cm or so beyond shower enclosure, which made me wonder. Or is that only if on a wood floor?
Similar Threads - waterpoofing concrete floors Forum Date
Floor Tiling On Concrete - Several Questions About Floor Prep and Laying DIY Tiling Forum Dec 27, 2018
Drying time for rapid set concrete please Natural Stone and Thin Porcelain Tiling Dec 2, 2018
Find a Tiler Post a Job Tile Events Tile Pics Blog Adhesive Poll Handy Downloads