Concrete and screed are similar in some respects. They are both made from the same basic materials: cement, water and aggregate (sand, stone or gravel). But, when it comes to their uses as building materials, concrete and screed are very different. Quality concrete is used for construction and structural tasks, while screed is applied as a top layer to a concrete base.
Physical differences between concrete and screed
Concrete and screed are both made from a mixture of cement, water and aggregate. The main difference between the two materials is the type of aggregate that is used.
When we are mixing concrete, we add coarse aggregate like gravel to the mix. These small stones are normally 20mm or less in size. This coarse aggregate gives the concrete its strength, durability and workability, and makes it suitable for structural work.
For screed, we don’t use the gravelly aggregate that we put in our concrete. Instead, we use fine, sharp sand, with a maximum grain size of about 4mm. This is what gives screed its fine, tightly packed texture and makes it suitable for applying as a top layer to a concrete floor.
At Rapid Readymix, we only ever use separated virgin aggregate in our concrete and screed mixes. This is why we can guarantee the quality of our BSI-certified concrete and screed.