Lay concrete screed correctly

Concrete screed is an extremely stable, load-bearing and load-bearing base course as well as being slightly cheaper than most commercially available screeds. Concrete screed is made from a mixture of sand, gravel and cement. Grain sizes are important here - as a rule, they are between 0 and 8 mm in grain size, when thin coatings with a height of up to 40 millimeters are produced, but higher aggregates usually also use a larger grain size up to 16 millimeters of grain. Cement is added according to the necessary strength, the highest achievable strength for concrete screed is approximately 450 kg per square centimeter - so it is a particularly stable base course. One can mix concrete screed without problems, but should pay attention to the grain sizes and the mixing ratio. The automatic mixing and conveying by a screed machine helps a lot when it comes to the installation speed.

Processing concrete screed

Like cement screed, concrete screed must also be compacted and smoothed immediately after installation. This is best done with a concrete screed with a float. Unlike the cement screed, the installation height and the scale of the concrete screed must be checked even more frequently. The rubbing and smoothing is mainly used to close the surface. This must be done very carefully, as remaining water esters can seriously affect the drying and the subsequent screed quality. Careful work is required here, the more experienced you are with this type of installation, the easier it will be for you to go by the hand. As a rule, concrete screed is applied almost exclusively as a composite screed, which means that an adhesive layer must first be applied to the substrate beforehand. Even before the application of concrete screed, cables and pipelines must always be covered by a leveling screed, which then supports the primer for the non-positive connection of concrete screed and substrate.

post processing

Concrete screed has some special features when it comes to drying. It must be kept completely free of air movements and temperature fluctuations during the first three days, otherwise the setting process will be disturbed. Then you have to keep a concrete screed wet for seven days to prevent drying out.

Video Board: Laying and levelling a sand and cement floor screed over underfloor heating using a spirit level