Ground preparation for floor coverings includes, among other things, grinding concrete and screed surfaces. This process is particularly gentle on the material and achieves very consistent results that hardly need to be reworked. The following article shows how and why concrete or screed is ground and what advantages grinding has over other methods.
How does the grinding of concrete and screed work?
A grinder for concrete and screed is equipped with a rotating grinding disc that is set in motion by a motor. Machines with a diamond coating are ideal, as they can grind down even hard concrete well.
When grinding, the device moves back and forth horizontally on the surface and cuts into the ground with a specific grit to smooth it. Leveling distances of 1-2 millimeters are possible. For a perfect result, the grit is doubled with each pass.
It is important that the grinder moves continuously over the floor and that constant pressure is applied in order to achieve an even result. Cross movement is ideal. The resulting dust should be extracted immediately to prevent health hazards.
What is the purpose of grinding screed and concrete floors?
Sanding screed and concrete floors is an integral part of subfloor preparation and serves both practical and aesthetic purposes. This often requires several grinding passes. If waterproofing agents are introduced into the concrete floor between these passes, grinding can replace sealing.
However, grinding can also be necessary, for example, if the screed is too high and the doors can no longer be closed properly.
Even if the screed is to receive a new coat of paint, it is necessary to sand the surface beforehand. Sanding before plastering the floor is also recommended. The sanded, smooth surface means that the layer of plaster does not have to be as thick, which saves both work and money.
What are the advantages of grinding concrete and screed compared to other processes?
If only small amounts of material are to be removed so that milling is not necessary, grinding concrete or screed is sufficient. It has a number of advantages over other methods: Among other things, grinding is much gentler on the material than milling, because the device does not penetrate so deeply into the concrete / screed. It is therefore not necessary for a new concrete construction to take place afterwards.
At the same time, very good adhesion values and high shear strength can be achieved through grinding, and the surface appearance is also better compared to shot peening. Due to the large processing width of modern grinding machines, a large area output per hour can be achieved without unsightly blasting or milling paths.
Specialist company for concrete and screed work for over 25 years
The substrate preparation of floor coverings is one of the main tasks in our company for concrete and screed work. Our employees have extensive expertise and many years of experience and ensure that the preparation of the substrate is carried out quickly and professionally so that your project can progress quickly. Simply make an appointment for a consultation and let us know how we can help you. We look forward to contributing to your new floor with our work.
Questions and answers about grinding
The aim of the grinding is to give the screed an adhesive surface on which a floor covering (with adhesive) is to be fixed. A single-disc machine (e.g. with 16 grit) is usually used for this, which removes loose material and roughens the surface. If, on the other hand, there are bumps in the screed, this must be ground down - for example with a so-called diamond rotary disc. The purpose of grinding is to smooth out unevenness and to remove light impurities on the surface. In addition to safety aspects, aesthetic aspects are particularly important here.
Only after complete drying and setting is it possible to grind a new concrete floor. Depending on the composition of the concrete, this can take up to 4 weeks. Old concrete floors can be sanded at any time, they should only be in a swept clean condition.
Since it is the only floor covering, the fair-faced screed must always be sanded. For example, it is only by sanding that the patterns created when using different colored cements can be optimally brought out. In order to obtain an aesthetically pleasing surface, several work steps are often necessary: After milling, the sanding takes place with different grit, which is ideally doubled with each pass (example: pass 1: grit 160, pass 2: grit 320)
The costs are usually calculated per square meter and depend on the amount of work. If we can support you with your project, we would be happy to make you an individual offer after a personal consultation. Simply contact us by telephone or e-mail.