In article , Rob
writes

"in2minds" wrote in message
...
need to level off a couple of dips in the floor before I lay a
floating floor
can anyone recommend a self levelling compound or would B&Q's (£6
for 25kg) be as good as any other ?

How deep are your dips, and what's the floor made of?


it's concrete and the worst is up to 15mm but mostly around 5mm

LJ

I recently levelled a concrete floor before laying wood laminate and
had problems with several cheap levelling compounds. Wickes was the
worst, B&Q and Plycolay were slightly better. The worst ones seem to
have more sand, which separates out and makes spreading a thin layer
difficult.
With 15mm dips I'd have thought levelling compound was pushing it a
bit. My worst areas were less than 10mm, but according to Evode/Bostik
Findlay's Technical dept., the usual max. thickness for levelling
compound is 5mm, and it's not usual to build up greater thicknesses in
layers. They suggested adding sharp sand (2 parts compound to 1 sand)
to the mix to lay a thick layer, but this makes it hard to achieve a
smooth surface and feather edges. In effect it reduces its
self-levelling properties and makes it into more of a screed, which is
what is usually used on very uneven areas. They recommended something
called Evostik Fast and Easy for up to 10mm thickness. Apparently it
comes in 20kg bags at about £30 from Focus or Homebase, but I didn't
try it.
I had a problem with cracking after drying, which is a sign of poor
adhesion, apparently. The worst areas also loosened and had to be done
again, but I eventually put up with some cracking if it didn't sound
hollow when tapped.
It all ended up being a bit of a nightmare job, and although I did say
never again, if I were to do another room I'd consider the latex type
of levelling compound.
Good luck!

Rob



Ardit works very well, but so it should at the price it is!...
--
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