After the installation of your new screed floor, the building must be sealed for 48 hours to prevent any draughts making contact with the surface of the floor. It should also be protected from very low temperatures and direct sunlight.
After the 48 hours, the floor may walked upon and stud work can be erected after 7 days, however, take care to ensure that nothing is left on the surface of the screed, storing materials such as polythene or sheets of plasterboard on your new floor will hinder the drying process significantly.
When using calcium sulphate screeds, after the initial 48 hours protective time, the building should be vented, allowing air to circulate over the floor.
It is recommended to avoid any fluid spills on the new floor as the screed behaves in a similar manner to a sponge and will absorb the liquid inhibiting the drying progress. Calcium sulphate screeds under ideal conditions will dry at a rate of 1 mm per day up to a depth of 40 mm and then 0.5 mm thereafter.
Adhesives and Primers
When choosing a tile adhesive, please make sure that it is compatible with calcium sulphate screeds, it should be gypsum based. We recommend AnhyFix.
After the floor has had the laitance removed and is completely dry, a suitable acrylic primer should be used such as Balfix APD. Alternatively, contact your floor covering manufacturer for advice.
After 7 days, your underfloor heating system switched on to an ambient temperature 20 – 25 degrees celsius. After 48 hours you can then increase the temperature by 5 degrees celsius per day up to a maximum of 50 degrees celsius. Leave the system running at this working temperature for 7 days, before gradually reducing it back down to ambient by 5 degrees a day.
Your underfloor heating should be off for a minimum of 48 hours before tiling and kept off for 14 days after tiling. It can then be brought up gradually to the operating temperature desired.
Please note that it is essential that prior to any bonded floor covering being applied to your new screed floor that the surface laitance is completely removed and your floor is completely dry. Laitance Removal and Moisture Testing are both services offered by Gyvtec Ltd. Please see our OTHER SERVICES page for details.