Short answer: choose liquid screed for larger open areas and floors with underfloor heating, where flatness, speed and heat transfer matter most. Choose a traditional sand and cement screed for smaller rooms, bonded floors onto concrete, floors that need falls, or where a cement-based surface is needed for the finish.
Side-by-side comparison
| Liquid (calcium sulphate) | Sand and cement | |
|---|---|---|
| How it is laid | Pumped, self-levels | Pumped or barrowed, compacted and hand-finished |
| Typical floating depth | From about 35 mm (homes) | From 65 mm (homes) |
| Over underfloor heating | Excellent contact and response | Good, fibre recommended |
| Flatness | Very high | Depends on the screeder’s skill |
| Area laid per day | Very large | Smaller |
| Before tiling | Sand off laitance, test, prime | Test moisture; usually ready to tile once dry |
| Wet areas and falls | Limited | Well suited |
Cost: it is not just the price per square metre
Liquid screed material usually costs more per square metre, but it can be laid thinner and much faster, and it dries ready for floor coverings sooner over underfloor heating. On large floors the overall cost is often similar. On small areas, the fixed cost of a liquid screed delivery can make sand and cement better value.
Our advice
Send us the floor area, build-up, heating type and finish you want. We will tell you which system suits it and why.
Which suits your project?
- Kitchen extension with underfloor heating, 30 m² or more: usually liquid screed, for flatness, faster heat-up and a thinner build-up.
- Small cloakroom or utility room: usually sand and cement. A liquid delivery is hard to justify for a few square metres.
- Bonding onto an existing concrete slab: sand and cement, laid as a bonded screed.
- Wet room with falls to a drain: sand and cement, which can be shaped to falls.
- Large commercial floor on a tight programme: either, depending on the finish, loading and timescale. This is where a site visit pays off.
What homeowners often miss with liquid screed
A calcium sulphate liquid screed must have its surface laitance sanded off before most floor finishes, and needs a compatible primer before tiles are fixed with cement-based adhesives. Leave that out and tiles can debond. Ask whoever lays your tiles to confirm they know the screed type.
See our liquid screed and sand and cement screed pages for how we lay each one.
Written by Ben Phillips, director of Chelmsford Floor Screeding Ltd, floor screeding contractors based in Billericay with 20+ years of experience across Essex and London. More about us.