Estimate sand/cement screed or self-levelling screed quantities, plus cost — metric or imperial.
Required screed thickness depends on the screed system, substrate, loading and project specification. Enter the specified design thickness below - this selector does not change it automatically.
Typical planning range is roughly 25-75mm depending on bonded/unbonded/floating construction - confirm your required thickness against your project's specification.
Editable planning assumption for the difference between finished, compacted screed volume and the loose dry ingredient volume needed to produce it. Actual yield depends on materials, grading, moisture, mixing and compaction - verify for your material/specification. 1.3 is a starting estimate, not a universally correct figure.
Separate from the dry-volume/yield factor - covers over-ordering/waste, applied after the yield adjustment.
No single ratio is universally correct - presets are common starting points, not a specification. Both sand and cement parts must be greater than zero (a 0:1 or 1:0 ratio isn't a normal sand/cement screed mix).
Typical planning estimates for bagged/loose material - adjust for your specific product.
Leave a bag weight at 0 to see total weight only, without a bag count.
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Choose Sand/Cement Screed for a traditional trowelled screed, or Self-Levelling for a poured/pumped compound. On the Sand/Cement tab, enter your area (or calculate it from length × width) and thickness, an editable dry-volume/yield factor, a separate material allowance, and your mix ratio - it calculates the volume at each step, splits it into sand and cement, and shows bags if you enter bag weights. On the Self-Levelling tab, use the coverage-per-bag method with your product's stated coverage, or the consumption-rate method with a stated kg/m²/mm rate. Check the Cost tab for a material cost estimate, priced separately for sand, cement and self-levelling compound.
Finished, compacted screed volume is not the same as the loose dry ingredient volume needed to produce it, so this calculator applies an editable dry-volume/yield factor first, then a separate material allowance for over-ordering/waste, before splitting into sand and cement by your mix ratio.
Each volume is then converted to weight using density, and to a bag count using your bag weight - the same approach used for base/sand/mortar materials elsewhere on this site. The dry-volume/yield factor is an editable planning assumption, not a universally correct figure - actual yield depends on materials, grading, moisture, mixing and compaction.
Self-levelling (liquid) screed compounds vary considerably in density and yield between manufacturers, and are normally specified by the manufacturer either as a coverage area at a given thickness, or as a consumption rate (weight per area per mm of thickness). The Self-Levelling tab offers both methods, using your entered product data directly rather than a geometric mix-ratio calculation.
Sand/cement screed. A 20 m² floor at 50mm thickness: finished screed volume = 20 × 0.05 = 1.000 m³ (1,000 L). With a 1.3 dry-volume/yield factor: dry ingredient volume = 1.300 m³. With a 10% material allowance: purchase volume = 1.430 m³. Split 4:1 sand:cement: sand volume = 1.144 m³, cement volume = 0.286 m³. At 1,600 kg/m³ sand and 1,400 kg/m³ cement: sand weight ≈ 1,830kg (74 bags at 25kg), cement weight ≈ 400kg (21 bags at 20kg).
Self-levelling screed (coverage method). A 20 m² floor with a bag covering 4 m² and 0% waste needs CEILING(20 ÷ 4) = 5 bags; with a 10% waste allowance, area with waste = 22 m², needing CEILING(22 ÷ 4) = 6 bags.
The most common mistake is applying a sand/cement mix-ratio calculation to a self-levelling product, or vice versa - the two are estimated completely differently (geometric mix ratio versus manufacturer-stated coverage/consumption rate) and mixing them up produces an inaccurate estimate. Another frequent error is treating finished screed volume as equal to the dry ingredient volume needed to produce it, or combining the dry-volume/yield factor and material allowance into one hidden figure instead of two separate, editable assumptions. It's also worth confirming your mix ratio and thickness against the project specification rather than assuming a single "standard" ratio, since the optional Construction type selector is contextual guidance only and does not change the thickness you enter.
This calculator estimates material quantity from the area, thickness, dry-volume/yield factor, material allowance, mix ratio and coverage/consumption data you enter. It does not determine structural suitability, required screed thickness, bonded/unbonded/floating system design, substrate preparation, primer/bonding requirements, damp-proofing, moisture condition, underfloor heating design, reinforcement, movement joints, drying/curing time, floor loading, or building-code compliance. Yield factor, mix ratio, thickness and density defaults shown are typical planning estimates only - confirm your specific product and project requirements separately.
Multiply your floor area by your target screed thickness to get the finished screed volume, apply an editable dry-volume/yield factor to estimate the loose dry ingredient volume, add a separate material allowance, then split that adjusted volume into sand and cement using your mix ratio (for a traditional sand/cement screed), or use a coverage-per-bag or consumption-rate method (for a self-levelling compound). Use the tabs above for an automatic calculation.
Commonly referenced presets are 3:1, 4:1 and 5:1 sand to cement by volume, with 4:1 often cited as a general default - but no single ratio is universally correct, so confirm the ratio against your project's specification, as it affects strength and workability.
Finished, compacted screed volume is not the same as the loose dry ingredient volume needed to produce it - the dry-volume/yield factor is an editable planning assumption for that difference, and actual yield depends on materials, grading, moisture, mixing and compaction. Material allowance is a separate, independently editable figure for over-ordering/waste, applied after the yield adjustment - the two are never combined into one hidden number.
Typical thickness depends on whether the screed is bonded, unbonded, or floating (over insulation or underfloor heating), and ranges roughly from 25mm to 75mm in common planning references - thinner bonded screeds and thicker floating screeds. The optional Construction type selector is contextual guidance only and does not change the thickness you enter - confirm your required thickness against your project's specification.
Self-levelling (liquid) screed is a pourable or pumpable compound that finds its own level and is typically much thinner than a traditional trowelled sand/cement screed. This calculator offers two methods: coverage per bag at your target thickness (from the manufacturer's data), or a consumption rate (weight per area per mm of thickness) - manufacturer data overrides generic assumptions either way.
A commonly cited general reference for traditional sand/cement screed is roughly 1mm of drying per day for the first 40mm of thickness, and slower for thicker screeds - but actual drying time depends heavily on thickness, ventilation, temperature and humidity. Self-levelling compounds often have manufacturer-stated drying/curing times that can be considerably faster. This calculator does not calculate drying time - confirm against your product's technical data sheet.
Screed cost depends on type (sand/cement vs self-levelling), thickness, and local material prices. Sand, cement and self-levelling compound are priced separately on the Cost tab - they are normally alternative screed systems, not materials purchased together for one screed; installation labour and any pumping/mixing equipment are priced separately.
No - it estimates material quantity only. It does not determine structural suitability, required screed thickness, bonded/unbonded/floating system design, substrate preparation, primer/bonding requirements, damp-proofing, moisture condition, underfloor heating design, reinforcement, movement joints, drying/curing time, floor loading or building-code compliance - confirm those against your project's specification or a qualified professional.