The Difference Between Screed and Concrete
Concrete and screed are two commonly used construction materials, but what exactly is the difference between them?
Concrete is a mixture of cement, water, aggregates and sometimes admixtures. It is typically used for structural purposes such as foundations, floors, walls and beams.
Screed, on the other hand, is a thinner mixture of cement and aggregates, without any water. It is often used as a leveling layer between the subfloor and the floor finish.
So, in short, the main difference between concrete and screed is their thickness and composition.
Concrete and screed are used in the construction industry across the globe, and they are similar in some respects. They are both made from the same basic mixture: cement, water and aggregate (sand, stone or gravel).
But, when it comes to their uses in construction, there are several key differences. Quality concrete is used for construction and structural tasks, while screed is applied as a top layer surface to a concrete subfloor.
What is the physical difference between concrete and screed?
Floor screed and concrete are both made from a mixture of cement, water and aggregate. The main difference between these them is the type of aggregate that is used.
When we are mixing concrete, we add hard core aggregates like gravel to the mixture. These small stones are normally 20mm or less in size. This provides strength, durability and workability, and makes it suitable for structural work. It also results in a coarser mixture.
For screed, we don’t use the same coarse aggregate – instead, screeds are sand and cement mixtures. We use fine, sharp sand, with a maximum grain size of about 4mm, mixed in with the cement. This is what provides its fine, tightly packed texture and makes it suitable for applying as a top finishing layer to a concrete floor.
At Rapid Readymix, we only ever use separated virgin aggregate in our concrete and traditional sand screed mixes. This is why we can guarantee the quality of our BSI-certified concrete and floor screeds.