Yes, ready-to-use microcement is perfectly compatible with underfloor heating. In fact, it is one of the best materials for this purpose. However, a heating protocol must be followed to prevent cracks in the flooring due to temperature changes.
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The heating protocol is as follows:
1. Turn on the heating at least 4 weeks after placing the cement mortar.
2. Maintain the water entering the circuits at 25°C throughout 2 or 3 days. Then gradually increase the water temperature to 45°C and keep it on for several days.
3. Turn off the heating for at least 48 hours before starting the microcement application. The maximum floor temperature should be 18°C.
Microcement floors should be applied to cementitious mortars that have reached an advanced setting stage. This occurs after three or four weeks drying-out, depending on the weather. In any case, it is essential that the mortar is practically dry. To achieve this, there should be a maximum of 5% humidity in the support, which must be checked with a relative humidity meter.
We recommend using quality self-levelling cement mortars.
Supports with powdery mortars are not at all suitable, since the base state for the application must be consistent, if otherwise then the base should be consolidated.
After applying the microcement, at least 48 hours should pass before the heating is gradually turned on (+5°C each day).
Always change the temperature gradually, both at the beginning and at the end of the heating period.
Make sure that the relative air humidity in the rooms is not too low.
Always avoid an accumulation of heat caused by rugs and carpets, or the lack of space between the furniture and the floor.
Important! Between the floor and the vertical faces there will always be a joint to permit dilation. Failure to comply with this indicated requirement may result in cracking.