Ordering the right number of bricks can save you hundreds of pounds and prevent frustrating delays. Too few bricks means stopping work mid-project and paying extra delivery charges. Too many leaves you with piles of unused materials cluttering your garden.
🧱 Brick Calculator
Quickly estimate the number of bricks needed for your wall project in the UK
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A brick calculator helps you work out exactly how many bricks you need for walls, extensions, garages, or garden projects. You’ll get an accurate estimate in minutes, not hours of confusing manual calculations.
This guide shows you how to use a brick calculator properly, which measurements matter, and how to account for waste and mortar. Whether you’re a DIY enthusiast planning a garden wall or a builder pricing a job, you’ll learn the practical steps to get your brick quantities right first time.
What Is a Brick Calculator?
A brick calculator is a tool that works out how many bricks you need based on your wall dimensions and brick size. You enter the length, height, and thickness of your wall, and the calculator tells you the total number of bricks required.
Most calculators also factor in mortar joints (the gaps between bricks) and allow you to add a percentage for wastage. This gives you a realistic figure that accounts for broken bricks, cuts, and mistakes.
Brick calculators come in three main forms:
- Online calculators – Free web tools where you input measurements and get instant results
- Mobile apps – Handy for on-site calculations when you’re at the builders’ merchant
- Spreadsheet templates – Downloadable Excel or Google Sheets files you can customise
The maths behind these calculators is straightforward, but doing it manually leaves room for errors. Automated tools remove the guesswork and speed up your planning.
Why Accurate Brick Calculations Matter
Getting your brick count wrong affects both your budget and project timeline. Here’s what happens when calculations go astray.
Cost Implications
Bricks typically cost between £300 and £700 per thousand, depending on type and quality. Ordering 10% too many on a project requiring 5,000 bricks means spending £150–£350 on materials you don’t need.
Delivery charges add another layer. Most suppliers charge £50–£150 per delivery. If you underestimate and need a second delivery, you’re paying twice.
Project Delays
Running out of bricks mid-build is frustrating. You can’t continue until new stock arrives, which might take days or weeks if your chosen brick isn’t readily available. This delay costs money if you’ve hired tradespeople by the day.
Colour Matching Issues
Bricks from different batches can vary slightly in colour. If you order more bricks later, they might not match your existing wall perfectly. This creates an uneven appearance that’s particularly noticeable on house fronts.
According to the Brick Development Association, colour variation between batches is normal, making it essential to order all your bricks at once from the same production run.
Brick Sizes and Types
Different brick sizes and types affect how many you’ll need. UK bricks follow standard dimensions, but variations exist.
[Insert image: Diagram showing standard UK brick dimensions with measurements labelled]
Standard UK Brick Dimensions
The standard UK brick measures 215mm long × 102.5mm wide × 65mm high. When you add a 10mm mortar joint on all sides, the working size becomes 225mm × 112.5mm × 75mm.
This standardisation makes calculations simpler, but always check your actual brick dimensions, as some manufacturers produce slightly different sizes.
Common Brick Types
| Brick Type | Typical Use | Size Variation |
|---|---|---|
| Standard facing brick | External walls, visible surfaces | 215 × 102.5 × 65mm |
| Common brick | Internal walls, concealed work | 215 × 102.5 × 65mm |
| Engineering brick | Foundations, damp-proof courses | 215 × 102.5 × 65mm |
| Thin brick | Cladding, feature walls | 215 × 102.5 × 20–50mm |
| Reclaimed brick | Restoration, character projects | Varies (often 225 × 110 × 70mm) |
How Brick Orientation Affects Quantities
Bricks can be laid in different patterns (bonds), which changes how many you need:
- Stretcher bond – Most common, shows the long face of bricks
- Header bond – Shows the short end, uses more bricks
- Flemish bond – Alternates headers and stretchers for decorative effect
- English bond – Alternates rows of headers and stretchers
Stretcher bond is most efficient and uses fewer bricks. Decorative bonds can increase requirements by 10–20%.
How to Use a Brick Calculator: Step-by-Step Guide
Follow these steps to get accurate results from any brick calculator.
Step 1: Measure Your Wall Dimensions
You need three measurements:
- Length – Measure along the base of where your wall will stand
- Height – From ground level (or foundation) to the top of the wall
- Thickness – Usually one brick length (half brick, 102.5mm) or two brick lengths (full brick, 215mm)
Measure in metres for easier calculations. A typical garden wall might be 5 metres long, 1.5 metres high, and 102.5mm thick.
Dealing with Multiple Walls
For rooms or structures with multiple walls, calculate each wall separately, then add the totals together. This is more accurate than trying to work out the perimeter as one calculation.
Step 2: Account for Openings
Windows, doors, and other openings reduce the number of bricks needed. Measure each opening’s width and height, then multiply to get the area.
Example: A door opening 0.9m wide × 2m high = 1.8m² of wall space you don’t need to brick.
Most brick calculators have a section where you can input these deductions.
[Insert image: Wall diagram showing how to measure around door and window openings]
Step 3: Enter Your Brick Dimensions
Input the actual dimensions of your chosen brick. Don’t assume standard sizes if you’re using reclaimed, imported, or specialist bricks.
Remember to include or exclude mortar joints depending on what the calculator asks for. Some calculators automatically add mortar joints; others expect you to input the working size (brick plus mortar).
Step 4: Add Wastage Percentage
Always add extra bricks for wastage. A good rule of thumb:
- 5% wastage – Experienced bricklayers on straightforward projects
- 10% wastage – Average DIY projects or complex designs
- 15% wastage – Beginners, intricate patterns, or cutting-heavy designs
Wastage covers broken bricks, cutting errors, and future repairs. It’s better to have a few left over than to run short.
Step 5: Review and Adjust
Check the calculator’s output makes sense. A single-skin garden wall 5m long × 1.5m high typically needs around 700–750 bricks including wastage.
If the number seems wildly off, recheck your measurements and confirm you’ve entered dimensions in the right units (metres vs millimetres).
Manual Brick Calculation Method
Understanding the manual calculation helps you verify calculator results and work out quantities when you don’t have internet access.
The Basic Formula
Number of bricks = (Wall area ÷ Brick area) + Wastage
Here’s how to work through it.
Calculate Wall Area
Wall area = Length × Height
Example: 5m × 1.5m = 7.5m²
Calculate Brick Area (Including Mortar)
One brick with mortar = 0.225m × 0.075m = 0.016875m²
This is the standard working size for UK bricks in stretcher bond.
Divide Wall Area by Brick Area
7.5m² ÷ 0.016875m² = 444.4 bricks
Round up to 445 bricks for the main wall.
Add Wastage
445 × 1.10 (10% wastage) = 489.5, rounded up to 490 bricks
Accounting for Wall Thickness
For double-skin walls (full brick thickness), you need twice as many bricks. Simply multiply your result by two.
Single-skin example: 490 bricks
Double-skin: 490 × 2 = 980 bricks
Quick Reference: Bricks per Square Metre
For fast estimates, remember these figures:
| Wall Type | Bricks per m² (excluding wastage) |
|---|---|
| Single skin (half brick) | 60 bricks |
| Double skin (full brick) | 120 bricks |
| Header bond (single skin) | 75 bricks |
Multiply your wall area by these figures, then add your wastage percentage.
Calculating Mortar Requirements
Bricks need mortar to hold them together. Getting this quantity right prevents mid-project trips to the builders’ merchant.
How Much Mortar per Brick?
Each brick typically requires about 2–3kg of mortar when laid with 10mm joints. For 1,000 bricks, you’ll need approximately:
- 12–15 bags of cement (25kg each)
- 1–1.2 tonnes of building sand
- Plasticiser (follow product instructions)
The mortar mix ratio affects quantities. A common mix is 1:5 (one part cement to five parts sand) for general brickwork above ground.
Mortar Calculator
Many brick calculators include mortar estimation. If yours doesn’t, use this formula:
Mortar volume = (Wall area × Joint thickness) × 1.15
The 1.15 multiplier accounts for mortar wastage and compression.
The Marshalls building materials website offers detailed guidance on mortar mixing ratios for different applications.
Common Brick Calculation Mistakes to Avoid
Even experienced builders make these errors. Watch out for them.
Forgetting About Wall Returns
When walls meet at corners, you need extra bricks for the return (the bit that turns the corner). Add the length of any returns to your total wall length before calculating.
Ignoring Piers and Columns
Decorative piers or support columns use additional bricks. Calculate these separately based on their dimensions and add them to your wall total.
A standard pier might be 440mm × 440mm × 1.5m high, requiring around 180–200 bricks.
Not Measuring Multiple Times
Measure twice, calculate once. A small measurement error becomes a large materials error when multiplied across an entire wall.
Using the Wrong Units
Mixing metres and millimetres is a common mistake. Stick to one unit throughout your calculation. Most calculators prefer metres for large dimensions and millimetres for brick sizes.
Underestimating Wastage
Five percent wastage sounds generous but often isn’t enough. Bricks break during delivery, cutting, and handling. Ten percent is safer for most projects.
Practical Examples: Brick Calculations for Common Projects
Here are real-world examples to help you understand how calculations work in practice.
Example 1: Garden Wall
Project: A single-skin garden wall
Dimensions:
- Length: 6 metres
- Height: 1.2 metres
- Thickness: Half brick (102.5mm)
Calculation:
- Wall area: 6m × 1.2m = 7.2m²
- Bricks needed: 7.2 × 60 = 432 bricks
- Add 10% wastage: 432 × 1.10 = 475 bricks
Order: 500 bricks (rounded up to typical pack sizes)
Example 2: Garage Extension
Project: Double-skin garage wall with door opening
Dimensions:
- Wall: 5m long × 2.4m high
- Door opening: 2.5m wide × 2.2m high
- Thickness: Full brick (215mm)
Calculation:
- Total wall area: 5m × 2.4m = 12m²
- Door opening area: 2.5m × 2.2m = 5.5m²
- Actual brick area: 12m² – 5.5m² = 6.5m²
- Bricks needed (double skin): 6.5 × 120 = 780 bricks
- Add 10% wastage: 780 × 1.10 = 858 bricks
Order: 900 bricks
[Insert image: Garage extension showing door opening and brick wall construction]
Example 3: House Extension Front Wall
Project: Double-skin wall with window
Dimensions:
- Wall: 4m long × 2.7m high
- Window: 1.5m wide × 1.2m high
- Thickness: Full brick (215mm)
Calculation:
- Total wall area: 4m × 2.7m = 10.8m²
- Window area: 1.5m × 1.2m = 1.8m²
- Actual brick area: 10.8m² – 1.8m² = 9m²
- Bricks needed (double skin): 9 × 120 = 1,080 bricks
- Add 10% wastage: 1,080 × 1.10 = 1,188 bricks
Order: 1,200 bricks
Choosing the Right Brick Calculator
Not all brick calculators are created equal. Here’s what to look for.
Essential Features
- Multiple measurement units – Should accept metres, feet, inches, and millimetres
- Mortar joint customisation – Lets you adjust joint thickness
- Wastage options – Allows percentage adjustments
- Opening deductions – Includes fields for doors and windows
- Different brick sizes – Works with non-standard dimensions
Bonus Features
- Mortar calculation
- Cost estimation based on brick prices
- Project saving and sharing
- Mobile-friendly design
- Printable results
Recommended Calculator Options
Look for calculators from reputable sources like builders’ merchants, brick manufacturers, or established construction websites. The Federation of Master Builders recommends using calculators that follow British Standards for accuracy.
Free online calculators work well for most projects, but professional builders might prefer dedicated apps with offline functionality and project management features.
Advanced Brick Calculations
Some projects need more detailed calculations. Here’s how to handle complex scenarios.
Cavity Walls
Modern house walls typically use cavity construction with two skins of bricks separated by an insulation gap. Calculate each skin separately:
- Outer skin (facing bricks): Calculate as single-skin wall
- Inner skin (common bricks): Calculate as single-skin wall
- Total bricks = Outer skin + Inner skin
A 10m² cavity wall needs approximately 60 facing bricks and 60 common bricks per square metre, plus wastage.
Curved Walls
Curved walls use more bricks because of the cutting and positioning required. Add an extra 20–30% wastage for curved sections.
The tighter the curve, the more waste you’ll generate. Consider using special curved bricks for tight radius work.
Feature Walls and Patterns
Decorative brickwork patterns like basket weave, herringbone, or soldier courses increase brick requirements. These patterns:
- Use more bricks per square metre
- Generate more cutting waste
- Take longer to lay
Add 15–25% extra bricks for patterned work, depending on complexity.
Steps and Retaining Walls
Steps need careful calculation:
- Calculate treads (horizontal parts) separately from risers (vertical parts)
- Account for coping bricks on top of walls
- Add extra for foundations if building on slopes
Retaining walls often need engineering bricks at the base for strength. Calculate these separately using the appropriate area.
Brick Types and Their Impact on Calculations
Choosing the right brick affects both quantity and cost.
Facing Bricks
Used for visible external walls. They come in various colours and textures. Standard dimensions apply, but premium ranges might vary slightly.
Facing bricks cost £400–£1,200 per thousand depending on style and quality.
Common Bricks
Used for internal walls and hidden work. Cheaper than facing bricks at £300–£500 per thousand.
Common bricks follow standard dimensions, making calculations straightforward.
Engineering Bricks
Dense, strong bricks for foundations and areas exposed to water. Available in Class A and Class B grades.
Engineering bricks cost £500–£800 per thousand and typically follow standard dimensions.
Reclaimed Bricks
Salvaged from old buildings. Sizes vary significantly, so measure carefully. Expect higher wastage (15–20%) due to damage and irregular dimensions.
Reclaimed bricks cost £800–£1,500 per thousand but add character to projects.
Thin Bricks (Brick Slips)
Thin facing tiles (20–50mm thick) used for cladding. Need specialist fixing. Calculate area coverage rather than traditional brick counts.
Thin bricks cover approximately 50–55 pieces per square metre depending on joint width.
Cost Planning with Brick Calculators
Once you know how many bricks you need, work out the total project cost.
Material Costs
Calculate total brick cost:
Number of bricks ÷ 1,000 × Price per thousand = Brick cost
Example: 1,200 bricks at £500 per thousand = £600
Add mortar costs:
- Cement: £7–£10 per 25kg bag
- Building sand: £40–£80 per tonne
- Plasticiser: £5–£15 per bottle
Delivery Charges
Most suppliers charge per delivery:
- Local delivery: £50–£100
- Long distance: £100–£200
- Crane offload (if needed): £150–£300
Order everything at once to avoid multiple delivery fees.
Labour Costs
Bricklayers typically charge:
- Day rate: £200–£300 per day
- Per brick: £0.50–£1.50 depending on complexity
- Square metre rate: £60–£90 per m²
An experienced bricklayer lays 300–500 bricks per day on straightforward work.
Hidden Costs
Don’t forget:
- Wall ties (cavity walls): £20–£40 per 100
- Damp-proof course: £15–£30 per roll
- Coping stones or bricks: £5–£20 each
- Lintels for openings: £30–£150 depending on span
- Waste removal: £100–£200 per skip
Environmental Considerations
Brick production and transportation have environmental impacts. Accurate calculations help reduce waste and carbon footprint.
Reducing Waste
Ordering the right quantity means fewer bricks end up in landfill. The construction industry generates 60% of UK waste, according to WRAP (Waste and Resources Action Programme).
Use your brick calculator to:
- Order precise quantities
- Minimise cutting waste through careful planning
- Reuse broken bricks for hardcore or landscaping
Sustainable Brick Choices
Consider environmental factors:
- Reclaimed bricks – Zero embodied carbon from manufacturing
- Local bricks – Lower transport emissions
- Modern efficient bricks – Better insulation reduces heating costs
- Lime mortar – More breathable and recyclable than cement mortar
Recycling and Reuse
Leftover bricks don’t need to be waste:
- Store properly for future repairs
- Use for garden edging or paths
- Donate to community projects
- Advertise on local selling sites
- Crush for hardcore base material
Working with Building Regulations
Brick walls must meet building regulations. This affects calculations.
Structural Requirements
Load-bearing walls need adequate thickness and strength. Check requirements:
- Single-storey buildings: Usually half-brick walls acceptable
- Two-storey buildings: Often need full-brick or cavity walls
- Three-storey plus: Require structural engineer calculations
Building Control will specify requirements based on your project.
Damp-Proof Courses
All external walls need damp-proof courses (DPC) to prevent rising damp. This adds to calculations:
- DPC sits two courses above ground level
- Use engineering bricks or plastic DPC membrane
- Calculate separately if using different brick types
Insulation Requirements
Modern buildings need high insulation standards. This affects wall design:
- Cavity walls: Include insulation between skins
- Solid walls: May need external or internal insulation
- Extensions: Must match existing building standards
These requirements don’t change brick quantities but affect overall wall thickness.
Planning Permission
Some brick structures need planning permission:
- Walls over 1 metre high next to highways
- Walls over 2 metres high elsewhere
- Listed buildings (any external work)
- Conservation areas
Check with your local planning authority before starting. The Planning Portal provides guidance.
Seasonal Considerations for Brick Projects
Weather affects both brick quantities and laying conditions.
Cold Weather
Frost damages wet mortar. In winter:
- Bricks absorb more water, need more protection
- Mortar takes longer to set
- May need frost-protection additives
- Expect slower laying rates (affects labour calculations)
Avoid laying bricks when temperature drops below 3°C.
Hot Weather
Summer heat causes rapid drying. This means:
- Mortar sets faster, reducing working time
- Bricks need pre-wetting to prevent mortar drying too quickly
- More mortar wastage from drying out
- Consider adding 5% extra mortar to calculations
Cover fresh work to prevent too-rapid drying.
Wet Weather
Rain disrupts bricklaying:
- Protect delivered bricks from saturation
- Cover fresh work overnight
- Avoid laying in heavy rain
- Wet bricks are heavier, slower to handle
Schedule projects for dry periods when possible.
Professional vs DIY: When to Use a Brick Calculator
Brick calculators benefit both professionals and DIY enthusiasts differently.
For DIY Projects
Use a brick calculator when:
- Building garden walls under 1 metre
- Creating planters or raised beds
- Adding decorative garden features
- Small repair jobs matching existing brickwork
Benefits:
- Prevents over-ordering on small budgets
- Helps price projects before starting
- Builds confidence with accurate numbers
- Reduces trips to builders’ merchants
For Professionals
Builders and contractors use calculators for:
- Quick on-site estimates
- Initial job quotes
- Materials ordering
- Checking apprentice calculations
- Project documentation
Professional calculators often integrate with:
- Estimating software
- Supplier ordering systems
- Project management tools
- Invoice generation
When to Get Professional Help
Some projects need expert input:
- Structural walls in buildings
- Retaining walls over 1 metre high
- Complex load-bearing structures
- Listed building work
- Large commercial projects
A structural engineer or architect can provide accurate specifications. Your brick calculator helps you understand their requirements and cost implications.
Brick Calculator Alternatives and Complementary Tools
Brick calculators work alongside other planning tools.
Building Calculators
Related calculators help complete your project planning:
- Block calculator – For concrete blocks in internal walls
- Mortar calculator – Detailed cement and sand quantities
- Aggregate calculator – For foundation materials
- Paint calculator – For finishing rendered walls
- Cost calculator – Overall project budgeting
Measurement Apps
Smartphone apps can help with initial measurements:
- Laser measure apps (using phone camera)
- AR measurement tools
- Photo-based dimension estimators
- Area calculators
These work best for quick estimates. Always verify with physical measurements.
Design Software
CAD and design software provides detailed planning:
- SketchUp for 3D visualisation
- AutoCAD for technical drawings
- Design apps show how finished projects look
- Some include built-in material calculators
Professional builders use these for complex projects.
Supplier Tools
Many builders’ merchants offer:
- Online brick calculators on their websites
- In-store calculation services
- Delivery planning tools
- Project planning appointments
These services are usually free and help ensure you order the right products.
Tips for Ordering Bricks
Once you’ve calculated quantities, follow these ordering tips.
Timing Your Order
Order bricks:
- 2–3 weeks before starting work
- Earlier for specialist or reclaimed bricks
- During off-peak seasons for better availability
- All at once to ensure batch matching
Checking Deliveries
When bricks arrive:
- Count packs to verify quantity
- Check for damage (expect 2–3% broken)
- Inspect colour consistency across packs
- Refuse delivery if major damage or wrong products
- Photograph delivery for records
Storage
Protect bricks properly:
- Stack on pallets or wooden planks (not on bare ground)
- Cover with waterproof sheeting
- Leave space for air circulation
- Don’t stack more than 2 metres high
- Keep different brick types separate
Well-stored bricks last indefinitely. Wet bricks can be used but need longer to lay and dry.
Returns Policy
Understand your supplier’s policy:
- Most accept returns of unused, undamaged bricks
- Restocking fees typically apply (10–20%)
- Some require original packaging
- Time limits often apply (28–90 days)
- Delivery charges usually non-refundable
This makes slight over-ordering less risky than under-ordering.
Troubleshooting Calculator Results
Sometimes calculator results don’t seem right. Here’s how to troubleshoot.
Result Seems Too High
Check these common errors:
- Units entered incorrectly (metres shown as millimetres)
- Wall thickness set to full brick when you need half brick
- Wastage percentage too high
- Openings not deducted
- Wall area entered twice
Divide your result by 60 (bricks per square metre). Does that match your wall area? If not, recheck inputs.
Result Seems Too Low
Possible issues:
- Forgot to include returns or piers
- Didn’t account for wall thickness correctly
- Mortar joints not included in brick size
- Multiple walls not all calculated
- No wastage added
Always add at least 5% wastage, even if you’re confident in your accuracy.
Different Calculators Give Different Results
Variation of 5–10% between calculators is normal because:
- Different mortar joint assumptions
- Rounding differences
- Varying wastage defaults
- Different brick size databases
Use the highest result or average the results for safety. The cost difference is small compared to running short.
Verifying with Manual Calculation
Do a quick manual check:
Wall area (m²) × 60 bricks per m² × 1.10 (wastage) = Total bricks
If this roughly matches your calculator result (within 10%), you’re on track.
Conclusion
A brick calculator transforms what could be a complex, error-prone task into a quick, accurate process. Whether you’re building a small garden wall or planning a large extension, knowing exactly how many bricks you need saves money, prevents delays, and ensures your project runs smoothly.
The key steps are straightforward:
Measure your wall dimensions carefully. Account for any openings like doors or windows. Enter accurate brick dimensions including mortar joints. Add appropriate wastage for your skill level and project complexity. Double-check the results make sense before ordering.
Remember that slight over-ordering is safer and cheaper than running short mid-project. The extra bricks give you insurance against breakage, cutting errors, and future repairs. Most suppliers accept returns of unused bricks, though restocking fees may apply.
Start with a reliable brick calculator, verify the results with manual calculations if needed, and order from a reputable supplier who can provide consistent batches. Your careful planning ensures your brickwork project succeeds without the frustration of materials shortages or the expense of excess waste.
The few minutes spent using a brick calculator properly can save you hundreds of pounds and hours of frustration. It’s one of the simplest tools that makes the biggest difference to any building project.
Frequently Asked Questions
How many bricks do I need per square metre of wall?
For a standard single-skin wall using UK bricks in stretcher bond, you need approximately 60 bricks per square metre including mortar joints. Double-skin walls require 120 bricks per square metre. Always add 10% wastage to these figures for realistic ordering quantities. Different brick sizes or laying patterns will change these numbers.
Can I use a brick calculator for block walls?
No, brick calculators are specifically designed for standard bricks. Concrete blocks have completely different dimensions (typically 440mm × 215mm × 100mm) and require far fewer units per square metre. Use a dedicated block calculator instead. You’ll only need about 10 blocks per square metre compared to 60 bricks.
What’s the best wastage percentage to use?
Use 10% wastage for most projects. Increase to 15% if you’re a beginner, working with reclaimed bricks, or creating complex patterns with lots of cutting. Experienced professionals on simple walls might manage with 5% wastage. Never order without wastage allowance, as some breakage during delivery and construction is inevitable.
Do I need to calculate mortar separately from bricks?
Most brick calculators that include mortar estimation are accurate enough for material ordering. As a general guide, you need approximately 12–15 bags of cement and 1 tonne of sand per 1,000 bricks when using a 1:5 mortar mix. Buy mortar ingredients in stages rather than all at once, as requirements vary with weather and working speed.
How do I calculate bricks for a wall with multiple windows?
Calculate each window opening separately (width × height) to get the area in square metres. Add all window areas together, then subtract the total from your wall area. Use the remaining wall area for your brick calculation. It’s better to calculate one wall at a time rather than trying to do the entire building at once, as this reduces errors.