Or: How to make self levelers obey the laws of physics

As we were talking about self leveling products in another thread, I thought it'd be a good idea to share some info on how to use them.

1. Read the data sheet and/or the instructions on the bag.

2. Priming correctly is important, because these products won't work at all if the substrate sucks the water out.

3. Very important, the mixing water needs to be as cold as you can get it. I know some applicators, who will run a hose through an esky filled with ice, just to get the water cold. If your water is warm it can flash-set the mixture.

4. Don't use a spiral mixer to mix a self leveling compound. You need to use a mixer like this: . These mixers will knock all the little lumps out of the mix.

5. Water ratio is critical. If the instructions say use 4.8 liters of water per 20 kg, then use 4.8 liters of water.

6. Make sure the substrate isn't hot as this can also flash set the compound.

7. Pour out the compound, if you need to spread it a bit with a trowel, then LEAVE IT ALONE to do it's thing.

8. Using a spiked roller will improve the result. (Thanks Sir Ramic)


If anyone has any other hints, throw them in.

Points 3 & 4 are new to me & might be part of the reason why I'm not fond of these products...cheers Frank.

I can understand about flash setting over there.....We dont have such issues here in the UK .
Interesting about the mixer choice, not sure I have seen one like that over here...any reasons why to use this type of paddle.?
A lot of tilers will use a spiked roller over here but not strictly needed unless laying vinyl floor covering but it can help spread the SLC and I have had great results with it.

You may well have a problem in the UK, where it doesn't set. At temperatures below 5deg C (air and/or substrates) the curing process will stop.

The normal, spiral type paddle is ok for adhesives, but it really only forms a vortex when you're mixing. Self leveling compounds contain anhydrous calcium sulfate (also used in anhydrite screeds), high alumina cement and accelerators (as well as retarders and a heap of other things). Sometimes these will cause lumps to form while mixing. The mixing paddle shown knocks these lumps apart to form a smooth mix.

Thanks for the input with the spiked roller. I completely forgot about them and I've updated the first post.

Cheers Frank, very informative , I am sure I have seen one of those paddles somewhere but cant find it now. I have found similar but not quite the same. I will keep looking.

this is the one I found
600MM THIN M/PDDLE 160MMDIA, Mixing Paddles, DRILL ACCESSORIES | Metal & Plastic online Metals4u

For UK users:

Vitrex Plaster / Paint Mixing Paddle : Tooled-Up.com

Draper H6 Type Mixing Paddle - 500mm: Amazon.co.uk: Electronics

Vitrex VIT102967 10 2967 Mixing Paddle - Vitrex available at Toolbox

Yeah just found them Frank. Gotta have the threaded end though so the Draper one is for me and found it under half that price here Draper 10358 DRAPER H6 TYPE MIXING PADDLE - 500MM from Lawson HIS UK

The Australian self leveler made and sold by bunnings is called lanko. It is by far the best I've
used and can be mixed wetter than the manufacturer reckomends so its like water and its just a pour and level. Agreed with Frank the area must be primed first. Also a little trick with this stuff if you want to make it fall add a little sand to it and mix it dryer.
Lanko.com.au - Comprehensive ranges of floor levellers, concrete repair and structural grouting mortars

have to agree with adam, have achieved the best results using lanko products. they also have a good range of slc products to choose from depending on where and why you are using it.