My question is it okay or normal after using semi- self leveling cement (ARDEX K-15) to level floors from feather edge to .75”, I notice spalling hairline cracks throughout the installation and I would like to know if this is going to ruin my efforts to level the floor before gluing down engineered wood flooring or will the glue negate the problem? The Ardex still seems to be adheared to the concrete floor underneath strongly but has spalling. The history on this project is a 1947 single story rambler slab on grade needed the old Bruce #8 Parquet Floor replaced so I took up the floor found that the mastic was probably hot applied tar very hard to remove so I used Soy bean based solvent and degreaser and a lot of scraping and absorbent material and MESS everywhere on everything and then rented a scarifier and grinder to get the floor totally prepared for leveling with Ardex. Whew!

Usually cracking occurs from rapid drying. Of Also too much water to the surface can cause cracking while curing..
If its hair line cracks, I wouldn't worry about it. Just as long as all areas of the floor is adheared to the underlying concrete.

Your answer sounds logical I tried to follow the mixing directions but this is an extreamly quick drying product. I used the primer primer letting it dry for three hours before applying the concrete. Anyway the concrete seems solidly adhered I am getting some Engineered wood flooring in a few weeks. Thanks for the answer.