Hi , I am using Mapei ultra fast screed on job s in retirement homes and when its dry their s very small cracks appearing in it when its dried. I am wondering whether this is due to the heat in the buildings and it has also happened when I have screened a room where the sun shines through a window on to the area that has cracked. Is this due to the screed drying to fast? It seems to be solid to the floor and it has also happen when the floor has been primed. I have feathered the cracked areas and laid vinyl on it and have had no come backs with floors yet. Any ideas?
Could be the drying time Have you been going over existing leveling compound by any chance or any glue residue or bitumen maybe ?
Id be thinking what your thinking in regards to heat within building drying it out faster than it should I know what them retirement homes are like bleeding tropical all year round, as long as its solid then feather and fit it imo
Rapid or fast drying levelling compounds will micro-crack due to drying out too fast, especially in warm conditions. A good tip is to prime the surface as soon as you can. that will slow it down, as daft as that sounds. Basically, cement formulations require the water to stay in the body of the material long enough to enable all of plasticisers, etc. to their job. too rapid a hydration will cause this type of cracking, however it will not normally compromise the bond. Hope this helps.
I'm not having this problem ? Also I wouldn't bother with a fast-track compound in warm weather or in a warm area It can go off on the bucket before it even get to the floor
I blame the builders that lay all the soft, poorly mixed screeds, and there are a lot of them around!
Totally agree When you go over a lot of slabs with a rebound hammer there well under 35nm some are under 20 and also there can be inconsistent strength throughout with soft spots NA everything eh Dan
