House Extensions
Add the space your home is missing — a bigger kitchen-diner, an extra reception or a whole new floor. We take extensions from first drawings through planning, foundations and build to a finished, guaranteed space.
The classic reason to extend — open-plan living and dining.
A new reception, playroom, utility or home office.
Bi-fold doors and roof lights transform how a home feels.
A well-built extension is one of the strongest investments going.
Why Handy 4 London
An extension touches almost everything — groundworks, structure, roofing, glazing, electrics, plumbing, plastering and decorating. We manage all of it in-house, plus the planning and building control, so you deal with one team and one quote rather than a string of separate contractors. We'll also guide you through permitted development, planning and any party wall agreement from the very first visit.
Find the Right Fit
The right choice depends on your home, your plot and how much space you're after.
Rear or side extensions that open up the ground floor — the most common way to add space.
Extend over two floors to add a room downstairs and a bedroom above in one project.
Combine a rear and side-return extension to dramatically open up the whole ground floor.
Fill in the alley beside a Victorian terrace to widen a galley kitchen — a London classic.
What's Included
How It Works
We survey your home and plot and design an extension that works for the space and your budget.
We confirm what approval you need and submit the application, handling the back-and-forth.
An engineer designs the foundations and steels, ready for building control.
Groundworks, structure, roof and glazing — the extension is built and made weathertight.
Electrics, plumbing, plastering and decoration, then a final building-regulations sign-off.
Budgeting
Every extension is quoted individually after a survey — these are the main things that shape the figure.
Floor area and whether you're going up one storey or two is the biggest factor.
Ground conditions, drains and access can all affect the foundations needed.
Bi-folds, roof lights and the level of finish make a real difference.
Fitting a new kitchen or bathroom within the extension adds to the spec.
Where We Work
We build extensions right across the capital, including:
Good to Know
Many single-storey extensions fall under permitted development, but there are size limits and conservation areas are stricter. We'll confirm at survey and handle any planning application.
It varies with size and type, but a single-storey extension is often around two to four months on site. You'll get a firm timeline with your quote.
It's where we fill in the narrow alley beside a Victorian terrace to widen the ground floor — a popular way to create a big open-plan kitchen-diner in London.
Yes. From groundworks and foundations to steels and roofing, it's all handled in-house, with structural calculations and building control arranged for you.
If you're attached to a neighbour or building near the boundary, often yes. We'll let you know and help you through the process.
Yes. Every extension is backed by our 12-month workmanship guarantee, and we're fully insured.
We cover Central, North and West London and the surrounding boroughs. Not sure if we reach you? Just ask.
Send us a message or call with a few details about your home and what you'd like to add. We'll arrange a free survey and follow up with a written quote.
Explore More
Tell us about your home and what you'd like to add, and get a free, no-obligation quote — from foundations to finish, handled by one team.