The main cementing material of gypsum-based self-leveling mortar is gypsum, and it has the performance of automatic leveling.

The ground leveled by it is accurate in size and extremely horizontal. Gypsum itself has the characteristics of micro-expansion. Using it as the basic material for self-leveling can make the leveled ground stable and greatly reduce the risk of cracking.
At the same time, gypsum-based self-leveling mortar is pumped for construction, which is very efficient. After the leveling is completed, the strength can reach more than 90% of the design strength in one day, and the decorative surface layer can be constructed in 1 to 2 days. A variety of floor materials can be laid on self-leveling mortar, including wooden floors, PVC plastic floors, floor paints, various tiles, marble, etc. However, it is also reminded here that tile laying cannot be carried out directly.

Gypsum-based self-leveling mortar can harden in a short time, and people can walk on it 4-6 hours after the mortar is poured. However, a thin layer of mortar will form on the surface during the hardening process. This layer is too weak to lay tiles. It also slows down the drying time of the mortar.
When cement-based adhesive is applied directly to the floor. The cement in the tile adhesive reacts with the gypsum in the self-leveling mortar. A mineral called calcium sulfonate is formed at the interface. The related structural changes are sufficient to completely separate the cementitious adhesive from the flattened base.

Therefore, before laying tiles on gypsum-based self-leveling mortar, necessary preparation measures should be taken.

To seal the porous surface of the gypsum base and prevent moisture from being absorbed from the tile adhesive. At the same time, it can avoid the adverse reactions that often occur between cement-based mortar and gypsum substrates.
Specifically, the primer spray can be used to seal and isolate between the gypsum self-leveling and the tile. It can be a hydrophobic emulsion. It can also be a reactive resin. Avoid problems such as poor bonding caused by direct laying.

Gypsum-based self-leveling mortar is used for floor leveling, which has advantages that other materials cannot match.

With the promotion of residential finished products. Building floor heating backfill, the application of ground lifting is also increasing. The lifting and leveling construction can be completed at one time with self-leveling mortar. And the use of floor heating backfill can also make the floor heating have better insulation and energy-saving effects during the application period.
But as we said before, a variety of floor materials can be laid on self-leveling mortar. However, when laying tiles, primer spraying and sealing isolation measures should be carried out to achieve a good floor laying effect.
HPMC for self-leveling mortar