To prevent cracking of the heating screed during its thermal movements add to it the BETOKAN plasticizer. The minimum screed thickness above a pipe is 4.5 cm (6.5 cm above the thermal insulation). With addition of the BETOKAN plasticizer to concrete the thickness of the concrete screed above a pipe can be reduced to 2.5 cm (6.5 cm above the thermal insulation).
In case of ceramic or stone sheet flooring, floor slabs transferring large loads we recommend to reinforce plates by laying on pipes 3 mm steel wire meshes with sieve apertures 10 x 10 cm. Reinforcement does not substantially affect the strength of a floor slab, however, occurring cracks or fissures in a plate limit its height and width. Within the area of expansion joints this reinforcement must be interrupted.
For floor slabs transferring large loads (greater than in residential buildings) select properly the height of a concrete screed and the kind of insulation so that its deflection does not exceed 5 mm.
Poured large surfaces shall be divided into smaller ones with expansion joints (minimum thickness 0.5 cm – expansion profile or an edge band) so that the length of a uniform plate is not above 8 m, its area not above 30 m2, and the relation of sides is 1:2.