Levelling a floor

bee27 · Post by **bee27** » Sun Aug 30, 2009 10:51 pm

Hi,

I'm going to start tiling my kitchen in the next week or so and lay underfloor heating. However the kitchen floor (concrete with some sort of screed) isn't perfectly level.

The screed seems to have curved up towards one of the corners of the room, and also up against an old stud wall for a pantry - which I ripped out. Where the stud was there are gaps in the screed that also need filling.

I have some thermal tile backer board from the underfloor heating supplier which I will be fitting using screws and wall plugs - as recommended by the supplier.

So I have a few questions...

Should I level the floor before laying the tile backer or level it after fitting the tile backer and underfloor heating cables?

What's the most cost effective method of levelling it?

Would you recommend levelling the whole floor or to smash away some of the screed and fill with cement / levelling compound where needed?

Thanks.

bathstyle · Post by **bathstyle** » Mon Aug 31, 2009 8:06 am

It really does depend how out of level the floor is. I would try to get it as flat as possible and repair any area with screed where necessary, get a spirit level over the floor, it doesn't need to be level- just flat.

I would glue the Thermal sheets down with a rapid setting tile adhesive, not screws, this will take out a lot of imperfections in the floor whereas screwing will not, there will always be voids.

Post a pic of the floor with a level on it, then we can decide the best way forward.

lamntile · Post by **lamntile** » Mon Aug 31, 2009 8:28 am

I had a similar situation when i remodelled my kitchen and back room with the screed missing from a couple of removed walls also had screed higher in corners.

I used a bolster chisel to get rid of the high corners/edges as they wernt that bad. Filled the gaps where the walls had been with cement. Job done and ready for flooring ;-)

bee27 · Post by **bee27** » Fri Sep 04, 2009 10:29 am

bathstyle & lamntile, thanks for your replies.

I've attached some photos of the floors. As you can see the areas where the old studs were and the corners are unlevel. However other areas of the floor are level.

I guess the best thing to do is what lamntile did.

Should I screw the boards down or use adhesive? I already have the plastic washers for use when screwing the boards and it will be cheaper than adhesive and more secure (according to the suppliers).

Thanks

bathstyle · Post by **bathstyle** » Fri Sep 04, 2009 2:29 pm

More pics please

I'm not too concerned about the floor being out of level, they always are.

You just need to make sure it is fairl yflat, so not too many dipps or bows in the floor, to be fair, it looks pretty good to me, just fill any voids with screed.

Edit, you need to glue and screw the boards, if you just screw down willy nilly there will be lips galore where the boards meet. At least this way you can adjust how far you screw each screw in, screw them in too far and the board may sink lower than the previous board. Once the adhesive is set, the screws can then be countersunk where necessary. Also the boards wont be very solid if you just screw.

It's one of those jobs that could end up going horribly wrong unless you have some sort of an idea of what you are doing.