Floor Screed Calculator

When a rough structural concrete floor is poured, it is rarely smooth enough or level enough to directly accept flooring finishes like tile, hardwood, or laminate. To solve this, contractors pour a thin layer of "screed" over the slab to create a perfectly flat canvas.

Unlike structural concrete, screed does not contain heavy gravel. It is simply a semi-dry mixture of Portland cement and sharp sand. By using our floor screed calculator, you can quickly estimate exactly how much sand and cement you need to purchase to level your room.

Our screed volume calculator determines your materials in two steps: finding the total volume, and separating it into the standard 1:4 mix ratio.

For example, if you have a 10x10 foot room and you need to pour a 2-inch thick leveling screed:

• Your total area is 100 square feet.
• A 2-inch thickness equals roughly 0.166 feet.
• 100 sq ft 0.166 ft = 16.6 cubic feet of total volume.
• Because screed uses a 1:4 ratio (1 part cement, 4 parts sand), exactly 20% of that volume will be cement, and 80% will be sand.

Running these calculations by hand is tedious, which is why our sand and cement screed calculator instantly converts these volumetric measurements into the actual weight (pounds or kilograms) of dry materials you need to buy.

When estimating your materials, ensure your planned thickness meets building standards:

• Bonded Screed (1.5" minimum): If you are pouring the screed directly onto a primed concrete slab where it will chemically bond to the floor, it can be poured as thin as 40mm (about 1.5 inches).
• Unbonded Screed (2" minimum): If you are pouring the screed over a plastic vapor barrier (DPM), it cannot bond to the slab. Therefore, it must be thicker (at least 50mm or 2 inches) to prevent it from cracking under its own weight.
• Floating Screed (2.5" minimum): If you are pouring screed over radiant underfloor heating pipes or soft acoustic insulation, it must be at least 65mm (2.5 inches) thick.