How Many Bricks Do I Need?
Estimating brick quantities accurately helps avoid costly over-ordering, project delays and mismatched material from a second purchase. Mortar joints affect how much wall area each brick covers, while cuts, breakage and layout changes make a waste allowance essential. This guide explains the full takeoff in plain language, including openings and a worked example. The free Brick Calculator performs the same calculations automatically in Imperial or Metric units.
What Does a Brick Calculator Do?
A brick calculator turns wall measurements and product dimensions into a practical purchase quantity. It starts with the entire wall, removes openings that will not receive brick and divides the remaining area by the wall face covered by one brick and its mortar joint.
The result is a material estimate, not a structural design. It helps plan the brick order and optional material cost while keeping each assumption visible.
- Gross wall area from wall length and height
- Door and window deductions
- Net wall area that will receive brick
- Required brick quantity based on brick size and mortar joint
- Additional bricks for waste
- Optional brick material cost
How Brick Quantities Are Calculated
Gross wall area = wall length × wall height. For several walls, calculate each wall separately and add the areas.
Door deduction = number of doors × door area. Window deduction = number of windows × window area. Measuring each opening is more accurate than using a standard allowance.
Net wall area = gross wall area − door area − window area. Never use a negative net area.
Brick face area including mortar = (brick length + joint thickness) × (brick height + joint thickness). Use consistent units throughout this step.
Required bricks = net wall area ÷ brick face area including mortar. Round the required quantity up, because partial bricks cannot be purchased as a complete unit.
Final brick estimate = exact brick requirement × (1 + waste percentage), rounded up. The waste allowance covers cuts, breakage, color sorting and layout adjustments.
Common Brick Size Reference Table
| System | Brick Type or Size | Typical Actual Dimensions |
|---|---|---|
| Imperial | Modular | 7 5/8 in × 3 5/8 in × 2 1/4 in |
| Imperial | Queen | 9 5/8 in × 3 5/8 in × 2 3/4 in |
| Imperial | King | 9 5/8 in × 2 3/4 in × 2 5/8 in |
| Imperial | Utility | 11 5/8 in × 3 5/8 in × 3 5/8 in |
| Metric | Metric size | 190 × 90 × 57 mm |
| Metric | Metric size | 215 × 102.5 × 65 mm |
| Metric | Metric size | 230 × 110 × 76 mm |
How Mortar Joints Affect Brick Count
Mortar joints occupy part of the finished wall face. Adding the horizontal and vertical joint thickness to the actual brick face creates the nominal module covered by each installed brick. A larger module covers more wall area, so the calculated brick count decreases slightly as joint thickness increases.
Common planning options are 3/8 in and 1/2 in in Imperial work, or 10 mm and 12 mm in Metric work. The specified joint can vary with the brick, bond, appearance, tolerances and project requirements. Confirm it with the plans, brick manufacturer or mason rather than choosing a joint solely to change the estimate.
Example: Bricks for a 20 ft × 8 ft Wall
Assume a 20 ft long × 8 ft high wall with one standard door, two standard windows, modular bricks, a 3/8 in mortar joint and 10% waste.
Gross wall area: 20 ft × 8 ft = 160 sq ft.
Door deduction: 1 × 21 sq ft = 21 sq ft.
Window deduction: 2 × 15 sq ft = 30 sq ft.
Net wall area: 160 sq ft − 21 sq ft − 30 sq ft = 109 sq ft.
Nominal modular brick face with joint: (7 5/8 in + 3/8 in) × (2 1/4 in + 3/8 in) = 8 in × 2 5/8 in = 21 sq in, or about 0.1458 sq ft.
Exact brick requirement: 109 sq ft ÷ 0.1458 sq ft per brick ≈ 747.4 bricks. Round up to 748 bricks before waste.
Waste-adjusted estimate: 747.4 × 1.10 ≈ 822.2. Round up to 823 bricks to buy.
This example uses standard opening allowances. Actual brick quantities vary with measured openings, brick dimensions, bond pattern, corners, cuts, breakage and installer technique.
Common Brick Estimating Mistakes
Avoid these common takeoff errors before ordering brick:
- Ignoring mortar joints and dividing by the brick face alone
- Skipping waste for cuts, breakage, sorting and layout changes
- Forgetting to deduct doors, windows and other large openings
- Using a nominal brick name instead of checking the actual manufacturer dimensions
- Mixing feet and inches or meters and millimeters in the same formula
- Rounding down instead of rounding the final purchase quantity up
- Assuming a simple running-bond estimate covers arches, corners, piers and special shapes
Tips for Buying Bricks
Order the calculated waste allowance with the main purchase instead of waiting to see whether you run short. A second order can add delivery cost and may not match the original color range.
- Buy from one manufacturing lot when practical to improve color and texture consistency
- Confirm actual brick dimensions, packaging quantities and pallet counts with the supplier
- Inspect delivered pallets and follow the supplier’s process for reporting damage
- Blend bricks from several pallets during installation when the manufacturer recommends it
- Save matching extras in a protected location for future repairs or additions
Brick Estimating Disclaimer
Use this guide and calculator as planning references. Final quantities can change with actual manufacturer dimensions, bond pattern, mortar joints, wall thickness, openings, returns, corners, cuts, breakage, special shapes and installer technique. Confirm the order with the brick supplier or mason before purchasing. Structural masonry, veneers, ties, reinforcement, lintels, flashing and foundations must follow approved plans, manufacturer instructions and local code.
Get an instant estimate with the Brick Calculator
Use the free Brick Calculator to estimate brick quantities, waste and optional material cost before purchasing.
Frequently Asked Questions
How many bricks are needed per square foot?
A modular brick with a 3/8 in joint covers a nominal face of about 8 in × 2 5/8 in, which works out to roughly 6.86 bricks per sq ft before waste. Larger Queen, King and Utility formats need fewer bricks per sq ft. Always calculate from the actual brick and joint dimensions.
How much waste should I allow for brick?
A simple wall may use about 5% waste, while 10% is a common planning allowance. Complex bonds, many corners, special shapes, matching requirements or fragile units may justify 15% or a project-specific allowance from the mason or supplier.
Should I round the brick quantity up?
Yes. Round the purchase quantity up to a whole brick after applying waste. Suppliers may sell by strap, cube or pallet, so the final order may need to round up again to the available package quantity.
What mortar joint thickness should I use?
Common planning joints include 3/8 in or 1/2 in in Imperial work and 10 mm or 12 mm in Metric work. Use the joint specified by the plans, manufacturer or mason because brick tolerances, appearance and project requirements vary.
How accurate is a brick calculator?
It provides a sound planning estimate when wall, opening, brick and joint measurements are accurate. Bond patterns, corners, cuts, breakage and special shapes can change the final quantity, so confirm the takeoff before ordering.
Can I estimate brick cost?
Yes. Multiply the waste-adjusted brick quantity by the supplier’s price per brick. Add delivery, pallets, mortar, ties, flashing, reinforcement, labor, tax and special shapes separately.
Why are there different brick sizes?
Brick sizes vary by manufacturer, product line, appearance, region and construction system. A larger brick covers more wall area and usually reduces the unit count, but names such as Modular, Queen and King do not replace checking actual dimensions.
Can I use Metric dimensions?
Yes. Keep wall dimensions in meters, brick and joint dimensions in millimeters, and convert the brick module to square meters before dividing. The free Brick Calculator handles native Metric sizes and conversions automatically.
Should I subtract every opening?
Measure and deduct large doors and windows. Small penetrations may not reduce the order because surrounding cuts and waste can use as much material as the opening saves. Follow the project takeoff method for unusual openings.