Microcement and Underfloor Heating

Why Microcement Works Well with Underfloor Heating

Underfloor heating is now standard specification in virtually all A-rated Irish new builds, and increasingly being retrofitted into renovated properties throughout Ireland. Microcement is one of the most UFH-compatible floor finishes available — its thin, cement-based application conducts heat efficiently from the floor slab to the room above, with minimal thermal resistance compared to thicker floor finishes.

The thermal conductivity advantage of microcement over tiles is measurable. Because the microcement system is only 2-3mm thick versus 10-20mm for a typical tile and adhesive installation, less thermal mass needs to be heated before the floor surface reaches the desired temperature. This means the UFH system reaches equilibrium faster, using less energy to heat a room to a given temperature.

Installation Sequence for New Builds

For new build projects in Ireland where microcement is specified over UFH, the programme should proceed as follows. The UFH pipes or mats are installed at ground floor level or first floor level by the mechanical contractor. The screed is then poured over the UFH installation and allowed to cure — a minimum of 4-6 weeks is required for a standard sand/cement screed to cure adequately. Before microcement application can begin, the UFH must be commissioned to drive off residual screed moisture. The moisture content of the screed must then be tested and must read below 4% before microcement is applied.

Commissioning After Application

Once microcement has been applied and the sealant has cured for a minimum of 7 days, the UFH can be commissioned or re-commissioned. A gradual temperature ramp is essential — starting at 15 degrees for two days, increasing to 20 degrees for two days, then gradually raising to normal operating temperature over the following week. This prevents thermal shock in the new microcement system.