Replacing floating floor - TilersForums.co.uk | Tile Forums

robster · 05-02-2008

Hi,

I need to replace a floating floor (about 20SqM) so that it can be tiled.

The current floor is 18mm T&G chipboard on 22mm polystyrene insulation. Between the chipboard and the polystyrene is a Damp Proof Membrane (poly sheet). The insulation sits directly on the concrete subtrate.

I was thinking of putting down bearers and noggins at 300mm centres then (after insulating the gaps) screwing down 18mm ply, with a DPM in between, and putting mastic in the screw holes to prevent compromising the DPM with the screws. I think this would work.

The other thought was to lay 40mm Marmox boards (or similar) which would bring the floor up to level, but I don't know how I would incorporate the DPM into this?

Any thoughts / ideas?

Many thanks.

GazTech · 05-02-2008

[quote=robster;53133]Hi,

I need to replace a floating floor (about 20SqM) so that it can be tiled.

The current floor is 18mm T&G chipboard on 22mm polystyrene insulation. Between the chipboard and the polystyrene is a Damp Proof Membrane (poly sheet). The insulation sits directly on the concrete subtrate.

I was thinking of putting down bearers and noggins at 300mm centres then (after insulating the gaps) screwing down 18mm ply, with a DPM in between, and putting mastic in the screw holes to prevent compromising the DPM with the screws. I think this would work.

The other thought was to lay 40mm Marmox boards (or similar) which would bring the floor up to level, but I don't know how I would incorporate the DPM into this?

Any thoughts / ideas?

Many thanks.[/quote]I think your first way is fine...and ready for tiling with flexi adhesive and grout......Gaz

tfs · 09-02-2008

Hi Mate,

If you are going to do this then I would suggest that you lay a sheet of DPM over the concrete and then your joist and noggings over this packing underneath to build up to level. (glue and packing firmly with gripfill or something)

Once this is done use the insulation board and cut it to sizes to fit tight between each joist, check that your insulation meets the required U Values.

At this point I would lay a chip board floor rather than plywood it at this point.

You will now have a suitable sub floor, now you can ply or whatever method you choose to do.

This is a method I have worked to in the past in accordance with an Architects spec.

If I can be of any help just email me mate.

kris