What if the subfloor is moist, or the concrete isn't dry enough?

Make sure that the root cause of the moist subfloor is solved first. Then, you can apply a liquid, damp-proof membrane (liquid DPM). If you want to glue down your vinyl floor, you will need to use a levelling compound, as a porous substrate is required for the glue.

• The moisture content of the subfloor must be less than 2,5%CM / 75%RH (cement screed) or less than 0,5%CM / 50%RH (anhydrite screed - subfloor).
• In the case of floor heating, results must be respectively 1,5%CM / 60%RH and 0,3%CM / 40%RH.

Always measure, record and keep your moisture content results.

A new cement screed floor must dry at least 1 week per 1cm (3/8”) thickness up to 4cm (1-1/2”). Thicknesses over 4cm (1-1/2”) require twice as much drying time. For example, a 6 cm (2-1/2”) concrete subfloor must dry at least 8 weeks.