How many bricks do I need for a single garage?

A standard single garage (3m x 6m internal) with 2.4m walls requires approximately 3,500-4,000 bricks for the outer skin alone. For cavity wall construction, double this for the inner skin, or use concrete blocks internally to reduce costs.

Do I need planning permission for a garage?

Detached garages under 30m2 with no sleeping accommodation often fall under Permitted Development. However, Building Regulations approval is almost always required. Attached garages always need Building Regs. Check with your local planning authority.

Should I use cavity wall construction for a garage?

Yes, cavity wall construction is recommended for UK garages. It provides better insulation, prevents damp penetration, and meets Building Regulations. Use a 50-100mm cavity with insulation batts or blown insulation.

What wastage should I allow for a garage build?

Allow 10% wastage for garage builds due to window and door openings requiring cut bricks. Increase to 12-15% if you have multiple windows or decorative features. Complex designs may need higher allowances.

What mortar mix should I use for a garage?

Use a standard 4:1 mix (4 parts soft sand to 1 part cement) above DPC. Below DPC, use a stronger 3:1 mix with waterproofer. Add plasticiser for improved workability. Never lay bricks in freezing conditions.

How deep should garage foundations be?

Garage foundations should be minimum 450mm deep and 450mm wide for standard single-skin walls, or 600mm wide for cavity walls. In clay soil or near trees, depths of 900mm-1200mm may be required. Always consult Building Control.

Can I build a garage myself?

Technically yes, but garage construction requires significant building skills including foundations, cavity walls, DPC installation, lintels, and roofing. Most DIYers hire professionals for structural elements and do finishing work themselves.

How much does it cost to build a brick garage?

A single brick garage costs approximately 15,000-25,000 pounds for materials and labour. A double garage typically costs 25,000-40,000 pounds. DIY can reduce costs by 30-40% but requires significant skill and time.

What size blocks should I use for the inner skin?

Use 100mm concrete blocks (440mm x 215mm) for the inner skin of a garage cavity wall. This is more economical than bricks and provides good thermal mass. Use 10.76 blocks per square metre in your calculations.

Do I need a lintel over the garage door?

Yes, a structural lintel is essential over the garage door opening. Use a concrete or steel lintel rated for the span - typically a 2.1m span requires a heavy-duty lintel. This must be specified in your Building Regs application.

Back to Brick Calculator

Brick Calculator for Garages

Building a garage? Calculate exactly how many bricks you need for single or double garage construction. Our calculator accounts for cavity walls, wastage, door and window openings, and UK Building Regulations requirements.

Bricklaying Materials Calculator

Calculate cement, sand and mortar using standard 4:1 ratio

1. Material Type

2. Wall Length (metres)

3. Wall Height (metres)

4. Waste Factor: 10%

Typical: 10% standard, 5% simple work, 15-20% complex patterns

Tips for Garage Construction

Most garages require Building Regulations approval and possibly planning permission
Cavity wall construction (two skins with insulation) is standard for UK garages
Allow for door opening - standard single garage door is 2.1m x 2.1m
Engineering bricks required below DPC level (minimum 150mm above ground)

Understanding Garage Construction

Building a brick garage is a significant construction project that typically requires Building Regulations approval. Most UK garages use cavity wall construction with an outer brick skin, insulated cavity, and inner blockwork skin for optimal weatherproofing and thermal performance.

Calculating Garage Bricks

To calculate bricks for a garage, you need to work out the total wall perimeter. For a standard single garage (3m x 6m external), the perimeter is 18 metres. Multiply by wall height and bricks per m2.

Cavity Wall Requirements

For the outer skin, use facing bricks (60 per m2). For the inner skin, most builders use:

100mm concrete blocks - 10.76 per m2, more economical
Standard bricks - 60 per m2, if matching throughout
Cavity width - typically 50-100mm with insulation

Example: Single Garage (3m x 6m)

Perimeter: (3 + 6) x 2 = 18m, Height: 2.4m
Wall area: 18 x 2.4 = 43.2m2
Less door opening: 43.2 - 4.4m2 = 38.8m2
Outer skin: 38.8 x 60 = 2,328 bricks (+ 10% = 2,561)
Inner skin: 38.8 x 10.76 = 418 blocks (+ 10% = 460)

Common Garage Sizes

Single Garage (3m x 6m)

Standard single car storage

- Perimeter: 18 linear metres
- Outer bricks: approx 2,500
- Inner blocks: approx 460

Large Single (3.5m x 7m)

Single car plus storage

- Perimeter: 21 linear metres
- Outer bricks: approx 3,000
- Inner blocks: approx 540

Double Garage (6m x 6m)

Two car storage side by side

- Perimeter: 24 linear metres
- Outer bricks: approx 3,500
- Inner blocks: approx 620

Large Double (6m x 7m)

Two cars plus workshop space

- Perimeter: 26 linear metres
- Outer bricks: approx 3,800
- Inner blocks: approx 680

Frequently Asked Questions

Find Local Suppliers

Enter your postcode to find local builders merchants

Related Calculators

House Extensions Boundary Walls

Need Professional Help?

Get quotes from trusted builders in your area.

Need a Custom Solution for Your Business?

Whether you're a contractor needing bulk calculations, a merchant wanting to embed our tools, or a business with specific requirements - we'd love to hear from you.

Or email us directly at [email protected]