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Subfloors : part III
THE SECRET OF THE SCREED BASIC CONDITIONS FOR A GOOD CEMENT-BOUND SUBFLOOR
It’s a truism to say that an attractive floor starts with the quality of the subfloor. A popular underlay is the traditional screed, also called a covering floor, subfloor, or wear floor. We’re talking here in particular about the layer fitted between the bearing floor and, in our case, laminate or parquet. What does a good screed consist of? The traditional cement-bound screed is the first thing which springs to mind. This consists of a mixture of sand, cement, and water which you use to achieve a perfectly level surface. You find a traditional screed in three variants: - The adhesive covering floor: This comes directly onto the concrete bearing floor and is the best option if the substrate is not porous and if there is no risk of cracks and rising damp.
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- The non-adhesive covering floor: This is fitted on a PVC foil or water defence partition. - The floating covering floor: This is fitted onto floor insulation with a thermal or acoustic function.
Calculating the drying time It’s important to realise that a traditional screed needs quite a long time to dry. The drying time depends on the thickness of the screed layer, the air humidity, and the temperature. To be precise, you can say that on average you should wait one week per centimetre, up to a thickness of 5cm, but that varies. If your screed exceeds 5cm, the drying will take about two weeks per centimetre. Logic is respected here, whereby the following principle holds: The
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