Self Levelling Compound Calculator
Takes the guesswork out of floor prep. Instantly calculate how many 20kg bags of self-levelling compound (SLC) or latex screed you need for your room.
Compound Estimator
Always round up. If your floor slopes from 2mm to 8mm, use 5mm average.
Optional: Adjust Product Settings
Default 1.5kg per 1mm per m²
Material Requirements
Getting Your Pour Right
Running out of self-levelling compound mid-pour is a DIY disaster. Because the compound begins to 'go off' (cure) within 15 to 30 minutes, you cannot stop pouring to run to the builders' merchant. You must have every single bag you need staged and ready before you mix the first bucket.
How The Maths Works
Almost all standard floor levelling compounds (like Setcrete, Bostik, or Mapei) share a very similar density and weight ratio after mixing.
The industry standard formulation ratio is 1.5 kilograms of dry powder per 1 square metre, per 1 millimetre of depth.
Floor Area (m²) × Depth Required (mm) × 1.5kg = Total Kg Needed
Tips for a Perfect Pour
- Prime Everything: Buy a specialist acrylic floor primer. Dilute it as per the instructions and roll it onto the subfloor the day before. This stops 'pin-holing' bubbles and rapid drying.
- Measure Your Water Perfectly: Do not guess the water ratio. Use a marked bucket. If the bag says 4.2 litres, use exactly 4.2 litres. Too much water ruins the structural integrity and causes a dusty white finish. Too little water stops the product 'self-levelling' across the floor.
- Use a Spiked Roller: As soon as you pour a puddle, roll over it with a spiked roller. This drags the compound smoothly over imperfections, breaks surface tension, and pops air bubbles to leave a glass-like finish.