Bricks & Blocks Calculator
Calculate bricks, sand and cement needed for walls. Accounts for openings and mortar joints.
By Konstantin Iakovlev · Founder, Calks.uk
Last updated: · Verified against HMRC and GOV.UK 2026/27 rates
Bricks Needed
523
Brick Cost
£261.50
Wall Area
8.4 m²
Sand
378 kg
Cement (25kg bags)
4
Disclaimer
This calculator is provided for informational purposes only and should not be considered as financial or tax advice. All calculations are performed locally in your browser — no personal data is collected or sent to our servers. Rates and thresholds are sourced from HMRC and GOV.UK and are updated for the current tax year. Always verify results with HMRC or consult a qualified professional before making financial decisions.
How It Works
The number of bricks needed depends on wall area, brick size and bond pattern. Standard UK bricks measure 215 × 102.5 × 65 mm. With a 10 mm mortar joint, you need approximately 60 bricks per square metre for a half-brick wall (single skin) in stretcher bond. A full-brick (one-brick) wall uses about 120 per m².
This calculator takes your wall dimensions, subtracts openings (doors, windows) and applies the correct rate per square metre. It also adds a wastage allowance — typically 5% for straightforward walls and 10% if there is significant cutting (such as around window reveals or corners with Flemish bond).
Enter the wall length, height, and the size of any openings. Choose the bond pattern and wall thickness. The calculator shows total bricks needed, bags of mortar (approximately 1 bag of cement per 35–40 bricks) and estimated cost. For large projects, order a sample panel first to confirm the brick choice and mortar colour.
How many bricks do you need? Single skin wall (½ brick thick): 60 bricks per m² (UK standard brick + 10mm mortar joints). Double skin (full brick wall, 215mm): 120 bricks/m². Sample wall 4m × 2m = 8 m² = 480 bricks single skin, 960 double. Always add 5-10% for cuts and breakages. Standard UK brick: 215×102.5×65mm. Engineering bricks slightly larger (215×102.5×73mm); used for footings, retaining walls due to higher strength and lower water absorption.
UK brick types and prices 2026. Common stock bricks: £400-£700/1,000 (40-70p each). Engineering bricks (Class A, B): £600-£1,200/1,000 — high-strength, dense, weatherproof. Facing bricks (decorative): £600-£1,500/1,000 — wide style range. Reclaimed Victorian/Georgian: £800-£3,000/1,000 — for conservation areas and period properties. Concrete blocks (cheaper alternative for inner skin): £1.50-£3.00 each, 100mm thick. Cavity wall structure: outer facing brick + inner concrete block + insulation in 50-100mm cavity.
Mortar — calculating sand and cement. Mortar volume: 0.7 m³ per 1,000 bricks (typical 10mm joints). Mix ratios: 1:5 (cement:sand) for above-ground walls; 1:4 for chimneys and high-strength; 1:3 for engineering brick footings; 1:6 with plasticiser for general work. 1m³ mortar = 250kg cement (5 × 25kg bags) + 1.25m³ sand. Average sand £40-£60/tonne (1m³ ≈ 1.6 tonnes). Lime mortar (NHL 3.5) for period properties and breathable walls: 3× cement cost but essential for solid-wall pre-1920s buildings.
Bricklaying productivity and labour costs. Skilled bricklayer lays 400-600 bricks/day (single skin facing wall). Engineering brick footings: slower, 300-400/day. Self-employed bricklayer UK 2026: £200-£350/day depending on region. Tools: trowel, spirit level, line and pins, plumb bob, string, mortar board, brick hammer, jointing tool. Tools cost £100-£200 entry-level. Apprentice work hours: 4-year apprenticeship at colleges (NVQ Level 2 or 3) — UK CITB-accredited courses.
Building Regulations and planning for brickwork. Garden wall under 1m: no permission needed. Garden wall over 1m adjacent to highway, 2m elsewhere: requires planning permission. Retaining walls retaining over 1.2m of soil: structural calculations required, often Building Control approval. Extensions and structural openings: Building Regulations apply, lintels and structural calcs required. Party Wall Act 1996: if working within 3m of neighbour's foundations or attaching to shared wall, must notify neighbour 2 months in advance. Solid wall insulation building regs: U-value 0.30 W/m²K target.
Example: Garden wall 6 m long × 1.2 m high, half-brick, one door opening 0.9 m × 2 m
- Total wall area: 6 × 1.2 = 7.2 m²
- Less opening: 0.9 × 1.2 (within wall height) = 1.08 m²
- Net area: 6.12 m² × 60 bricks/m² = 367 bricks
- Add 5% wastage: 386 bricks — order 400
Frequently Asked Questions
- How many bricks per square metre wall?
- Single skin wall (half-brick, 102.5mm thick): 60 bricks/m² with 10mm mortar joints (UK standard brick 215×102.5×65mm). Double skin (full brick, 215mm thick): 120 bricks/m². Cavity wall (outer skin facing brick + inner concrete block): 60 bricks/m² outer + concrete blocks for inner. Sample garden wall 4m × 1.5m × single skin: 6 m² × 60 = 360 bricks + 5% waste = 380. Always order from same batch (brick shade varies between firings).
- Mortar mix ratios — when to use which.
- 1:5 (cement:sand) — general above-ground brickwork, walls. 1:4 — exposed walls, parapet walls, chimneys (more weather-resistant). 1:3 — engineering brick footings, retaining walls (strongest). 1:6 with plasticiser — internal walls, less stressed work. Lime mortar (NHL 3.5 + sand 1:3): essential for pre-1920s solid-wall properties — allows moisture to evaporate through walls; modern cement mortar can trap damp. Use sharp sand for engineering work, soft sand for general bricklaying.
- Building Regulations for garden walls.
- Permitted development: walls under 1m next to highway, under 2m elsewhere — no planning needed. Above these heights: planning permission required. Structural: any wall retaining over 1.2m of soil needs structural calculations and Building Control approval. Foundations: minimum 600mm wide × 200mm deep concrete strip for walls up to 1.5m height; 750mm × 300mm for higher walls. Frost depth: minimum 750mm below ground for foundations. Movement joints every 6-8m for long walls (allows thermal expansion).
- How long does new brickwork take to dry and cure?
- Initial set: 1-2 hours (mortar firm enough not to fall out). Walkable: 24 hours (light contact only — don't disturb top courses). Full strength: 28 days (curing). Protect from rain for first 24 hours (rain washes mortar out of joints). Cover with hessian or polythene if heavy rain expected. Temperature: don't lay below 5°C — mortar won't cure. Above 30°C: mist water onto wall as you build to slow drying and prevent shrinkage cracks. Pointing (filling joints): typically done as you build (struck joint) or scraped back and re-pointed later (recessed).