House Extensions in London — Create More Space Without Moving
Moving house in London is expensive. An extension is often the smarter option — you get the extra space you need without the stamp duty, legal fees, and upheaval of buying somewhere new. At MIK Constructions Group, we design and build house extensions across London for homeowners who want more room to live, work, and grow. Whether you are adding a kitchen-diner, a new bedroom, a home office, or a larger living area, we handle the whole process from planning right through to the final coat of paint. We are based in Chadwell Heath and Mitcham, giving us strong coverage across East and South London. Every extension starts with a free on-site consultation and comes with full planning advice, a fixed price quote, and a one-year workmanship warranty.
- 1-year workmanship warranty
- Free on-site inspection
- Fully insured & 5-star rated
- Fixed-price written quote
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Tell us about your extension — we’ll respond the same day.
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Moving house in London is expensive. An extension is often the smarter option — you get the extra space you need without the stamp duty, legal fees, and upheaval of buying somewhere new. At MIK Constructions Group, we design and build house extensions across London for homeowners who want more room to live, work, and grow. Whether you are adding a kitchen-diner, a new bedroom, a home office, or a larger living area, we handle the whole process from planning right through to the final coat of paint. We are based in Chadwell Heath and Mitcham, giving us strong coverage across East and South London. Every extension starts with a free on-site consultation and comes with full planning advice, a fixed price quote, and a one-year workmanship warranty.
- 1-year workmanship warranty
- Free on-site inspection
- Fully insured & 5-star rated
- Fixed-price written quote
Types of House Extensions We Build in London
Every property is different. We work with you to design an extension that fits your home, your needs, and your budget.
Single Storey Extensions
The most popular choice for London homes. Ideal for extending a kitchen, creating an open-plan living space, or adding a utility room. We can build to the rear or side of your property, and most single storey extensions fall under permitted development.
Double Storey Extensions
Double the space for a fraction of the cost of a single storey build per square metre. A double storey extension can add a bedroom and bathroom upstairs while transforming your ground floor layout at the same time.
Side Return Extensions
Perfect for Victorian and Edwardian terraced houses, which typically have a narrow unused passage alongside the kitchen. A side return extension converts this dead space into a significantly larger ground floor living area.
Wrap-Around Extensions
Combining a side return and rear extension, a wrap-around gives you the maximum possible footprint on a single storey. It is transformative for properties with the right plot size and is one of the most popular options we build.
Rear Extensions
Extending straight back into the garden is the most straightforward approach for most homes. We handle everything from foundations to roof to interior fit-out.
- Ready when you are
Not Sure Which Extension Type Suits Your Home?
Book a Free Site Visit and We Will Advise
How Much Does a House Extension Cost in London?
Extension costs in London vary depending on size, specification, and the amount of structural work involved. Here are typical price ranges to help you plan.
Single storey rear extension
up to 4m
£25,000 to £50,000
Side return extension
–
£30,000 to £55,000
Double storey extension
–
£45,000 to £90,000
Wrap-around extension
–
£50,000 to £100,000+
Note! All our quotes are fixed price and include structural work, materials, labour, and project management. We do not add hidden costs once work has started.
Why Choose MIK Constructions for Your London Extension
Planning and Permitted Development Guidance
We advise you upfront on whether your extension needs planning permission or falls under permitted development. If planning is required, we can manage the application process for you.
Full Project Management
We coordinate every trade involved — groundworks, brickwork, roofing, electrics, plumbing, plastering, and joinery. You have one point of contact throughout.
Fixed Price and On Time
We quote fixed prices and set realistic timelines before work begins. No surprises on cost, no dragging out the job.
Fully Insured, One-Year Warranty
All extension work is covered by full public liability insurance and comes with a one-year workmanship warranty as standard.
Local and Reliable
We are based in East and South London and know the area well. We show up when we say we will and keep you updated throughout the job.
Join Hundreds of Happy London Customers
House Extension Services Across London
Ready to Build? Call (+44) 7888 256764 — Free Quote, No Obligation
East London
Stratford, Shoreditch, Hackney, Canary Wharf, Walthamstow, Bow
South London
Brixton, Peckham, Clapham, Greenwich, Wimbledon, Croydon
West London
Kensington, Chelsea, Notting Hill, Ealing, Hammersmith, Shepherd's Bush
North London
Camden, Islington, Hampstead, Highgate, Finsbury Park, Tottenham
- Ready when you are
Covering All London Postcodes — Call to Check Your Area
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Frequently Asked Questions About House Extensions in London
Still have a question? Call us on (+44) 7888 256764 — we are always happy to help
Do I need planning permission for a house extension in London?
Many extensions fall under permitted development, meaning planning permission is not required. However, this depends on the size, height, and location of the extension, and whether your property is in a conservation area or is listed. We assess this as part of your free consultation.
How long does a house extension take to build?
A single storey extension typically takes eight to twelve weeks from groundworks to completion. Double storey and wrap-around extensions can take twelve to twenty weeks depending on complexity.
Can I live in my home during the extension build?
In most cases, yes. We plan the build sequence to minimise disruption and keep your home liveable throughout. We will be clear upfront about any periods where access to certain rooms may be limited.
Will an extension add value to my home in London?
Yes. A well-built extension in London typically adds significant value — often more than the cost of the build. Kitchen extensions and extra bedrooms tend to deliver the best return.
What is the difference between permitted development and planning permission?
Permitted development rights allow homeowners to extend within certain limits without applying for planning permission. Planning permission is a formal application to your local council and is required for larger extensions or properties in restricted areas.
Do you handle the full build including electrics and plumbing?
Yes. We manage the entire project, including any electrical, plumbing, and heating work needed as part of the extension. You do not need to find separate contractors.
What kind of foundations do you use for extensions?
We carry out a site assessment to determine the right foundation type. Most extensions in London use strip or pad foundations. If the ground conditions require it, we may recommend pile foundations.
Can you match the extension to the existing brick and style of my home?
Yes. We source matching or complementary brickwork and materials to ensure the extension looks like a natural part of the original property rather than a bolt-on addition.
How much disruption will there be during the build?
There is always some noise and dust involved, but we keep the site clean and tidy throughout. We also protect internal areas and access routes so your daily routine is disrupted as little as possible.
Do you offer a warranty on extension work?
Yes, all our extension work comes with a one-year workmanship warranty. Structural elements also carry longer guarantees depending on the materials and methods used.
Book your free inspection.
Ready to Build? Call (+44) 7888 256764 — Free Quote, No Obligation
Phone/Whatsapp
(+44) 7888 256764
info@mikconstructionsgroup.co.uk
Office 1
Office No. 7495, 321-323 highroad, Chadwell heath, Essex, London RM6 6AX UK
Office 2
28A Hoylake Gardens Mitcham Surrey CR4 1ET
Get a Free Quote
Tell us about your extension — we’ll respond the same day.
No spam, ever. Replies in a few working hours.