1. What is a Paving Slab Calculator UK?

Definition: This calculator estimates the number of mortar bags needed for paving slab projects in the UK based on area, bedding depth, mortar ratio, and yield.

Purpose: It helps landscapers and DIYers determine how much mortar is required for patio and paving projects using standard UK measurements.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( M \) — Mortar bags needed (rounded up)
• \( A \) — Area to pave (square meters)
• \( D \) — Bedding depth (millimeters converted to meters)
• \( R \) — Mortar ratio (e.g., 4:1)
• \( Y \) — Yield per bag (cubic meters per bag)

Explanation: The area multiplied by depth (converted to meters) gives volume, adjusted by the mortar ratio, then divided by bag yield to get number of bags.

3. Importance of Mortar Calculation

Details: Accurate mortar estimation ensures proper slab bedding, prevents material waste, and helps budget for paving projects correctly.

4. Using the Calculator

Tips: Enter the area in m², bedding depth (typically 25-50mm), mortar ratio (often 4:1), and mortar bag yield (typically 0.017m³/bag). All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What's the typical bedding depth for paving slabs?
A: Most projects use 30-50mm bedding depth, but check manufacturer recommendations for specific slabs.

Q2: What mortar ratio should I use?
A: 4:1 (sand:cement) is standard for most paving projects in the UK.

Q3: How do I find my mortar bag yield?
A: Check the product packaging - most standard mortar bags cover about 0.017m³ when mixed.

Q4: Should I add extra for waste?
A: The calculator rounds up to whole bags, but consider adding 5-10% extra for complex patterns or cuts.

Q5: Can I use this for block paving?
A: No, block paving uses different installation methods - use a dedicated block paving calculator.