Self-Leveling Compound Calculator
Estimate self-leveling compound volume and bag quantity from floor area, average thickness and product yield. Use manufacturer data when available and keep the assumed waste allowance visible.
Compound inputs
Self-leveling compound requirement
How the self-leveling compound calculation works
The mathematical core is area multiplied by average thickness. This produces a placed volume in litres or cubic metres. The compound's density then converts volume to mass.
because 1 m² × 1 mm = 1 litre
Mass = volume × density
Why 1 mm equals 1 litre per square metre
A layer 1 metre long, 1 metre wide and 1 millimetre thick has a volume of 0.001 m³, which is one litre. That makes thin-layer flooring calculations especially convenient.
Worked example
For 45 m² at an average 6 mm thickness, the theoretical volume is 270 L. At 1.7 kg/L, that represents 459 kg. With an 8% planning allowance, the requirement is about 495.7 kg. At 25 kg per bag, 20 bags are required.
Why manufacturer yield is important
Commercial self-leveling compounds are formulated products. Published consumption can reflect the product's actual formulation, recommended thickness and installation method. When that information is available, it should take precedence over a generic density estimate for procurement.
Substrate variation
A floor that is visibly uneven can consume more compound than a nominal average suggests. Measuring the high and low points or using a detailed floor survey improves the thickness estimate.
What this calculator does not decide
It does not determine substrate preparation, primer selection, allowable maximum thickness, curing conditions, moisture limits, movement-joint treatment or floor-finish suitability.
Frequently Asked Questions
How much compound is needed per mm?
One square metre at 1 mm thickness equals 1 litre of volume.
Should average thickness be used?
Yes, when it accurately represents the planned installed layer.
Can I calculate bags?
Yes.
Should manufacturer yield override the density model?
Yes, when the published yield is applicable.