Levelling Compound

[TheLiberalLeft]

I need to lift a corner of a room - about 8m2 - by approx 12mm on average. It's to a concrete floor, and there will be carpet laid on top once it's level, so doesn't have to be the best/smoothest job in the world.

The levelling compounds seem very expensive. Anyone offer any advice?

[whitt]

I wonder if concrete would work that thin?

[eri]

i'm no engineer

but if you fill the floor with a minimum of 12mm concrete at the high corner going to a maximum of 24mm concrete at the low end you are going to need quite a bit of fine aggregate mix

but it should hold as 1 peice

however if you try to just lift the low corner by 12mm it will have to taper down to 0mm at the high end. that won't work with concrete because of the stones and without stones you've basically just got mortar which would crack if it were too thin

try googling "levelling cured concrete floors"

http://www.ehow.com/how_6073339_fix-unlevel-concrete-floors.html

http://www.ehow.com/how_6580595_fix-uneven-concrete-floor.html

[flyernzl]

Levelling compound is mixed with water and poured in as a liquid so it sets perfectly level (as the name implies). Yes it is expensive.

If you don't need it perfectly level, and it sounds as if you don't, you could use a patching compound. Ardurapid is one brand. These are trowelled in as a slurry and the smoothed off. Less expensive that a levelling compound, though still not spectacularly cheap.

If you are in Auckland, try talking to Flooring Wholesale Ltd. They're in Industry Road Penrose and deal in these type of products.

[sparxNZ]

i have used floor leveling compounds before and i think they are a complete rip off, basically they are just a bag of cement powder and sand with some plasticizers mixed in there to stop it from cracking if it is laid on a wooden floor - and it costs a fortune.

a mixture of sand, cement powder and water mixed to a consistency that will allow it to spread out and level without having to float it too much will work fine over a concrete floor.
it will shrink a bit as it dries and you might get some hairline cracks through it if you mix it too thin but if you are carpeting over it it doesn't really matter - it will still set hard.

cheers
sparx

[w44vi]

Normally if you are building up that much you would mix sand with the floor leveling, personally were it is over 20 mm I would screed with mortar (1 part cement to 4 parts sand) then floor level over the top of all you should prime the floor and use a bonding agent under the mortar
20 KG floor leveling = 3 M2 at 3 mm thick