Hello.
I'm in the process of casting the underfloor heating (waterborne Uponor) on my new floor (22 mm floor chipboard on 195mm joist c/c300) over 11m2.
The question... can I start by casting with fine concrete, and then apply a surface layer with self-leveling compound? I need to "float" 45mm so the cost adds up if I use all self-leveling compound.
Thanks for the answer...
I'm in the process of casting the underfloor heating (waterborne Uponor) on my new floor (22 mm floor chipboard on 195mm joist c/c300) over 11m2.
The question... can I start by casting with fine concrete, and then apply a surface layer with self-leveling compound? I need to "float" 45mm so the cost adds up if I use all self-leveling compound.
Thanks for the answer...
I would contact the manufacturer of the self-leveling compound. I know that certain types of compounds, at least many years ago, were used in precisely that way. They contain substances that chemically absorb moisture from the concrete beneath, so they could be used for "rapid drying" of a concrete pour. But if today's self-leveling compounds have that property, you should probably check with the manufacturers.
One problem otherwise with regular concrete is that it shrinks even long after it has dried out. So the fixture manufacturers typically specify that you cannot place tiles on a concrete surface until after at least 3 months, some say 6 months.
But it's conceivable that the self-leveling compound absorbs these shrinkage stresses.
One problem otherwise with regular concrete is that it shrinks even long after it has dried out. So the fixture manufacturers typically specify that you cannot place tiles on a concrete surface until after at least 3 months, some say 6 months.
But it's conceivable that the self-leveling compound absorbs these shrinkage stresses.
OK, will check with the manufacturer...
It does say on their website that if it's placed on "new concrete floor" it should be at least 3 months old... so there might be something to what you're saying.
But will check... Thanks.
It does say on their website that if it's placed on "new concrete floor" it should be at least 3 months old... so there might be something to what you're saying.
But will check... Thanks.
I haven't heard of leveling compound that supposedly dries up any concrete subfloor, but rather that leveling compound dries chemically even if it's installed under tiles, for example. Concrete and leveling compound have completely different shrinkage characteristics as they cure. I wouldn't use two different types of compound for embedding in your case, partly because it's always better to have a homogeneous layer, and partly because it will be applied on a plank floor. I would definitely use only leveling compound, and in your case, a good fiber-reinforced compound.