Smoothing and preparation of a floor for tiling.
Self-Leveling Compounds (SLC) are used to smooth and prepare the surface of a floor before applying a final coating such as ceramic, stone, porcelain tile, but also many other coatings.
slc is not intended for use as a final walking surface as the material will not withstand wear from foot traffic and can be applied from a feather edge up to 20mm thick with the addition of aggregate/granite. chips Some leveling compounds are suitable for exterior use and others for interior use only.
There are different types of slc and these have their particular use in different situations, more and more manufacturers are developing their type of specialized brand. I have used two different types of slcs:
- Water-based self-leveling compound.
- Acrylic-based self-leveling compound.
The water-based slc is a monocomponent compound that is mixed with a certain amount of cold and clean water; this amount of water can be slightly adjusted depending on air temperature and surface absorption.
The acrylic base is a two-part compound that must be mixed with the corresponding liquid polymer.
Open and dry times depend on many factors, but slow cure and set are easier to manage than fast set types. Always read the full instructions and guide usually found on the back of the product. Protective clothing is a must and that includes a proper face mask as SLCs are very dusty when mixed together and can cause respiratory complications.
Although the products are known as “self-levelers”, in practice it is not the same thing and smoothing compound is a more appropriate name.
For the novice and even some DIY experts, applying such a product can be quite a challenge and the best way to do it is to first mix a small amount and use it on a test area. Meet the “beast” before doing a medium or large job.
There are different ways to smooth floors using slcs and it can be applied by bucket pouring or pump. The latter is more appropriate on very large flats. So what tools do you need for small areas? Here is a list:
- clean buckets (1 for mixing, 1 for water, 1 for cleaning up spills)
- mixing paddle
- metal float (plastered)
- 6mm notched trowel (for even spreading)
- sponge
- power drill with mixing paddle or industrial adhesive mixer
- spiked shoes (if you need to walk on slc while smoothing)
- dust sheets (for access area protection)
- face mask
- gold latex rubber gloves
When mixing it with water you need to achieve optimum consistency as if you put too much water the slc will be too weak, also it won’t spread well as the heavier particles (sand) will fall to the bottom and the watery part will escape before you have time to say… “disturb”. π
If, on the other hand, the mixture is too hard, then it won’t spread on its own (unless you have so much that you can swim in it). π
Another thing to remember is that SLC can work its way through small cracks and gaps, so be sure to seal all of these areas before you start pouring it.
You can make it easier for yourself if you have a spiked roller and professional adjustable spreader.
The roller is to get rid of trapped air. It will help spread the compound a bit.
Using the adjustable spreader makes life so much easier as you can stand up and use it like a broom you will also see big improvements and since you use it standing up it makes the job go faster and saves your knees . multiple pins will even out bad areas better than your tile spreader. They come in different widths, but 80 cm is excellent for medium-sized household jobs.
A word of caution when using on u/f heating cables as you could damage the cables with this tool. Also be careful when using rollers as you can “spray” adjacent walls and furniture with leveling compound. Always move it very slowly and parallel to the object/wall/doors…
The best way to deal with leveling compound is to find out how much and where you need it. My approach is like this:
- 1) Place a cross laser level on a pole, extending the laser horizontally from one corner of the room to the opposite corner at a height of about 1.1m,
- 2) Then take a 1.2m spirit level and put it in front of the laser beam.
- 3) Making sure the spirit level is “plumb”, I make a mark where the laser shows on the spirit level.
- 4) from then on I can cross-reference that mark on the spirit level in dozens of places to see how good/bad the floor is.
You can also stick some broken tiles with suitable glue or sand and cement (depending on the height) as reference points to know how much to lift.
I hope this is useful information for some of you.