If you’re looking to create more living space, a 3-meter house extension in London can be a smart and cost-effective choice. Many homeowners can take advantage of Permitted Development house extensions without needing full planning permission, saving both time and money.

At Build Joy Limited, teams based in Hounslow and Harrow, we specialize in designing and constructing rear house extensions in London, making the process simple, fast, and stress-free for homeowners.

Can You Build a 3-Meter Extension Under Permitted Development?

Yes, but it depends on your property type:

• • Detached Homes in London – Can extend up to 4 meters under PD rights.

• • Semi-Detached & Terraced Homes in London – Can extend up to 3 meters under PD rights.

If your home is on designated land (such as a conservation area), you may face stricter rules. Always check with your local council or speak to experts like Build Joy before starting your London house extension project.

Making the Process Easier with Build Joy

We make your London home extension project:

• • Simpler – From approvals to construction, we manage the details.

• • Faster – Our experienced builders keep your project moving.

• • Cost-Effective – Clear, upfront pricing tailored to your needs.

Design & Cost Considerations

Functionality

A 3-meter rear extension in London is ideal for:

• • Kitchen-diners

• • Home offices or studies

• • Playrooms or utility rooms

Natural Light

Large windows, bi-fold doors, and skylights are popular in London rear extensions, bringing in natural light and improving comfort.

Materials

Choose from brickwork, render, or timber cladding. Your choice impacts the house extension cost in London and the overall look.

Pricing Example

For a 3-meter x 5-meter extension in London, Build Joy offers shell-only construction (air-tight and water-tight, no internal finishes) starting from £15,000 + VAT.

Exact costs vary depending on drawings, materials, and site conditions. A site visit is essential to confirm the price of your London house extension.

Where Do We Work?

We mainly cover areas within a 1-hour drive from our offices in Hounslow and Harrow, ideally inside the M25.

We also regularly complete house extensions in Buckinghamshire, Berkshire, Essex, and Surrey, depending on project scope.

Building Extensions in Winter vs Summer

Winter Advantages:

• • Contractors are less busy

• • Costs can be slightly lower

• • Permits are easier to obtain

• • Your home is ready by spring

Winter Disadvantages:

• • Foundations may be delayed due to frost

• • Slightly longer timelines until the roof is in place

• • Shorter working hours

Summer Advantages:

• • Faster overall progress

• • Better weather conditions

Summer Disadvantages:

• • Higher demand, builders book up quickly

• • Labour costs rise in peak season

FAQs – 3-Meter House Extension in London

1. Do I need planning permission for a 3-meter extension?
Not usually – most fall under Permitted Development house extension rules in London, but always check your property type and council guidelines.

2. How long does a 3-meter extension take to build?
On average, 8–12 weeks for shell construction, depending on weather, approvals, and complexity.

3. Can Build Joy handle drawings and approvals?
Yes – we have inhouse Architects and can help manage applications for Building Control approval or Structural related queries in London

4. What is Building Control, and do I need it?
Yes – even if you don’t need planning permission, all house extensions in London must comply with Building Regulations. This ensures your extension is structurally safe, energy efficient, and legally certified. Build Joy can guide you through this process.

5. How much will it cost?
A basic 3m x 5m London house extension shell starts from £15,000 + VAT, but final costs vary by design, materials, and site conditions.

6. Will a 3-meter extension add value to my home?
Yes – a well-built rear extension in London increases both space and property value.

7. Can I build an extension in winter?
Yes, but expect minor delays during groundwork due to weather.

8. Which areas does Build Joy cover?
We cover most of London within the M25, plus Buckinghamshire, Berkshire, Essex, and Surrey.

Ready to expand your home with a professional house extension in London?

Contact Build Joy Limited today for a free consultation and site visit.

Based in Hounslow & Harrow | Covering London + nearby counties

www.buildjoy.co.uk

At Build Joy Limited, teams based in Hounslow and Harrow, we specialize in designing and constructing rear house extensions in London, making the process simple, fast, and stress-free for homeowners.