Self Levelling Compound - anything but

[silverhornet]

Morning all and happy 2007!!!

Ok, I've just mixed and put down two bags of BAL Multibase to cover 10m2. The consistancy was the same as that on the wonderful DVD I received from the tile supplier. I pushed the SLC into the corners and coevered the whole area.......now I was under the impression that that should have been enough.

But this morning the floor isn't level - by quite some degree (corners nearly 6mm out) with sweeping trowel marks. The base was screed which had been left for 2 weeks to dry and then primed, the Multibase was mixed 5:1 by weight as per the instructions and mixed with a paddle attached to a drill, I took about 20mins to work the solution and used clean cold water and a wet clean float.

Now, I need to work out what to do. The tiles are being delivered on Friday and being no tiling expert (read as never having tiled before) I need the floor to be as level as possible.

I was thinking of getting one more bag of SLC, placing screws in the floor at 1.2m intervals and using these to level the erm, self levelling compound.

The main issue I have is that the room is 3.5m x 3m and so once I place the SLC in the far corners I can't adjust the level (as I was expecting the SLC to find it's own level) so are there any tips/hints on how to level this area or do I just go at it again?

Also do I need to prime the Multibase prior to putting the new bag on top?

Any help most appreciated

 

[gcol]

6mm isn't bad. Over what distance are you talking about? What length of straight edge are you using?
Bare in mind that the tile adhesive will cover most small irregularities. From the sound of it, your floor should be fine to tile on.

 

[silverhornet]

The 6mm was in a corner measured with a 1.2m length. However, I have now found a large mound which is about 8mm higher than the surounding area (the mound has a diameter of approx. 50cm) whih in turn is 6mm higher than one corner.

My plan of attack today is to chase in channels at the left and right hand side of the room and one in the centre (of a 3.5m room), screw down level 3mm batterns (or 2mm if I can find some today), identify the high and low spots, scrape/chisel the high spots down, prime and then apply some SLC on top.

Now that I know SLC needs more care than originally anticpated I'm hopeful that this will give me a near enough level surface - just when I thought I had seen the last of a dusty house!!!!