TryBuildCalcScreed Calculator for 100 Sq Ft (100 Sq Ft Floor Area Estimate)
Estimate screed for 100 sq ft of floor.
🕒 Last updated: August 23, 2026
Inputs
ℹ️Typical: 38-50 mm (bonded/unbonded), 65-75 mm (floating/underfloor heating)
Cost
For 9.29 m² of floor area, you need approximately 4 cement bags and 0.52 m³ of sand.
Screed Volume
Floor area: 9.29 m²
Wet volume: 0.465 m³
Dry volume (×1.33): 0.618 m³
Materials
Cement: 3.7 bags — buy 4 bags
Sand: 0.519 m³ (~0.83 metric tons)
Sand tonnage is approximate, using 1.6 tons/m³ average bulk density.
Order Summary — Theoretical vs. Order Quantity
| Material | Theoretical | Order Quantity |
|---|---|---|
| Cement | 3.6 bags | 4 bags (whole) |
| Sand | 0.494 m³ | 0.519 m³ |
Theoretical = before wastage. Order Quantity = after your 5.0% wastage allowance (cement rounded up to a whole bag).
Assumptions Used
Dry volume factor: 1.33 | Cement bag: 50 kg / 0.0347 m³ | Wastage applied once to cement bags and sand volume.
Bonded, unbonded, or floating — not sure which screed type applies here? Floor Screed Guide →
Tiling this floor once the screed has cured and dried? Tile Calculator →
Looking for the verification checklist, reference tables, tips, or common mistakes?See the complete Floor Screed Calculator.
100 sq ft floor screed quantity
A 10 ft × 10 ft floor is a common reference size for quick screed quantity comparisons — this page is pre-filled to that size.
Edit the Screed Thickness or Mix Ratio above to match your actual floor, and the material breakdown updates from the active values.
- Floor area: 100 sq ft (9.29 m²) before thickness is applied.
- Default mix: 1:4 standard screed at 50mm thickness.
- Scale this reference proportionally for larger or smaller floor areas.
Floor Screed Formula: How Is Cement and Sand Quantity Calculated?
Screed quantity is calculated from floor area and thickness, converted into dry volume, then distributed according to the cement:sand mix ratio.
Step 1 — Floor Area & Wet Volume
Floor Area = Length × Width
Wet Volume = Floor Area × Screed Thickness
Floor area is the plan area to be screeded. Wet volume is the actual mixed-screed volume needed to cover that area at the specified thickness.
Step 2 — Dry Volume Correction
Dry Volume = Wet Volume × 1.33
The dry volume factor accounts for sand bulking, voids between materials, and practical construction losses during mixing and application. Screed uses 1.33 rather than concrete's 1.54 because it contains no coarse aggregate.
Step 3 — Mix Ratio Distribution
Cement Volume = Dry Volume × (Cement Part ÷ Total Parts)
Sand Volume = Dry Volume × (Sand Part ÷ Total Parts)
Dry screed volume is divided according to the selected cement:sand mix ratio — 1:3 (heavy-duty industrial), 1:4 (standard), or 1:5 (light leveling only). Total Parts is the sum of both ratio parts.
Step 4 — Cement Bags Conversion
Cement Bags = Cement Volume ÷ 0.0347 m³/bag (50 kg bags)
One standard cement bag (50 kg) occupies approximately 0.0347 cubic metres. This conversion translates calculated cement volume into practical material procurement quantities.
Step 5 — Final Quantity with Wastage
Final Cement Bags = Cement Bags × (1 + Wastage %), rounded up to a whole bag
Final Sand Volume = Sand Volume × (1 + Wastage %)
Wastage is applied to both cement bags and sand volume for the practical order quantity — shown separately from the theoretical pre-wastage figures in the result card.
Worked Example
This example walks through your current inputs above, using the same steps as the Formula section.
Input Values Used
| Input | Value | Why it is used |
|---|---|---|
| Length × width | 10ft × 10ft | Sets the floor area to be screeded |
| Thickness / mix ratio / wastage | 50mm, 1:4, 5% wastage | Sets wet volume and splits dry volume into cement/sand |
Step 1 — Area & Volume
| Calculation | Substitution | Result |
|---|---|---|
| Floor area | 10ft × 10ft | 9.29 m² |
| Wet volume | 9.29 × 50mm | 0.465 m³ |
| Dry volume | 0.465 × 1.33 | 0.618 m³ |
Step 2 — Cement & Sand
| Material | Theoretical | Order Quantity |
|---|---|---|
| Cement | 3.6 bags | 4 bags (whole) |
| Sand | 0.494 m³ | 0.519 m³ |
Therefore, for 9.29 m² of floor at 50mm screed thickness and a 1:4 mix, you need approximately 4 cement bags and 0.52 m³ of sand.
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Disclaimer: This calculator provides approximate results for planning and estimation purposes only. Actual requirements may vary based on site conditions, materials, workmanship, and local building regulations. Always consult a qualified engineer, architect, or construction professional before making final decisions.