For many Fulham homeowners, the decision to do a house extension is not just a practical one — it is a statement of intent. A commitment to the home they have chosen, the neighbourhood they love and the life they want to build within it. Done properly, a house extension does not simply add space. It transforms the way a home feels, functions and endures.
At SM & Sons Construction, we work with a carefully selected number of homeowners across Fulham and south west London each year, delivering extensions that are built to the highest standard from the ground up. This guide covers everything you need to know about extending your home in Fulham — from costs and planning permission to timelines and what to expect from the process.
Why Fulham Homeowners Are Choosing to Extend
Fulham’s streets are lined with Victorian and Edwardian terraces — beautiful, characterful homes that were built for a different era. Many of them hold enormous untapped potential, particularly at the rear or along the side return. With property prices in the area remaining significant, the mathematics of extending rather than moving often make compelling sense. But for most of the homeowners we work with, this is about more than numbers.
It is about creating the open plan kitchen and dining space the family has always wanted. The extra bedroom that finally makes the house work properly. The flood of natural light that changes the mood of the entire ground floor. The home office that means the commute is simply a walk downstairs. A well considered house extension can redefine how a home functions every single day.
Types of House Extensions in Fulham
Rear Extensions
The most popular choice for Fulham terraced and semi-detached homes. A rear extension opens the back of the house up to the garden, typically transforming kitchen and living areas into something altogether more generous and connected. The difference in how the space feels before and after is often remarkable.
Side Return Extensions
Victorian terraces in Fulham frequently have a narrow alleyway running alongside the kitchen — a side return that goes largely unused. Extending into this space is one of the most effective ways to create a wider, more open ground floor plan. The results, when done well, are consistently stunning.
Wrap-Around Extensions
Combining a rear and side return extension into a single wrap-around project is the most ambitious and rewarding option for homeowners who want to fundamentally reimagine their ground floor. The increase in internal space and light can be transformative.
Double-Storey Extensions
Where the property and planning position allow, a double-storey extension adds bedrooms and bathrooms above while expanding living areas below — delivering exceptional value relative to the investment and significantly increasing the long-term worth of the property.
How Much Does a House Extension Cost in Fulham?
Construction costs in London reflect the complexity, specification and ambition of the project. As a general guide, house extension costs in Fulham sit within these ranges:
Single-storey extension: £2,200 – £3,000 per m² Side return extension: £65,000 – £100,000+ Wrap-around extension: £90,000 – £150,000+
These figures typically encompass groundworks and structure, roofing and insulation, windows and doors and first and second fix works. Kitchens, bathrooms and specialist finishes are generally costed separately depending on the level of specification involved.
What we would always caution against is treating these figures as anything more than a starting point. Every home is different. Every project has its own complexity, its own challenges and its own opportunities. A detailed site visit and a properly considered specification are the only reliable foundation for an accurate quote — and any builder who tells you otherwise is cutting corners before the work has even begun.
Planning Permission for House Extensions in Fulham
Many house extensions in Fulham fall within permitted development rights, which means planning permission may not be required. Whether this applies to your project depends on several factors including the type of property, the size and height of the proposed extension, its proximity to boundaries and whether your home sits within one of Fulham’s conservation areas.
Fulham has a number of conservation areas where permitted development rights are restricted or removed entirely. Even where planning permission is not required, building regulations approval is always mandatory and should never be treated as a formality.
We always advise homeowners looking to build a house extension in Fulham to establish their planning position early. The cost of getting this wrong later in a project — in time, money and stress — is entirely avoidable with the right guidance at the outset.
How Long Does a House Extension Take?
Timelines depend on the scope and complexity of the project, but a typical Fulham house extension follows a structure along these lines:
Design and planning: 6 – 12 weeks Single-storey construction phase: 10 – 14 weeks Larger extensions: 16 – 24 weeks
Factors that can affect these timelines include structural complexity, party wall agreements, access restrictions and material lead times. An experienced construction team will plan these variables carefully from the beginning rather than encountering them as surprises — which is why the quality of your pre-construction planning matters as much as the quality of the build itself.
Why Choose a Local Fulham Extension Builder?
Working with a construction company that has genuine local experience is not simply a convenience — it materially affects the outcome of your project. Familiarity with Fulham’s planning requirements, experience working on period Victorian and Edwardian properties, an understanding of access and neighbour considerations and established relationships with local suppliers all contribute to a project that runs more smoothly and delivers a better result.
At SM & Sons we have built that local knowledge over many years. It informs every project we take on and every recommendation we make.
Frequently Asked Questions
Do I need a party wall agreement for my extension?
If your extension involves or is close to a shared wall or affects a neighbour’s foundations, a party wall agreement will almost certainly be required. This is standard in Fulham’s terraced streets and something we help homeowners navigate as part of the process.
Will a house extension add value to my Fulham property?
A well designed and properly built extension will add meaningful value to your property — both in terms of market price and in terms of how the home functions and feels day to day. The key word is well designed and properly built. Quality of execution matters enormously.
Can I live in my house during the extension works?
In most cases yes, particularly for rear extensions. There will be periods of disruption and some homeowners choose to make alternative arrangements during the most intensive structural phases. We always discuss this honestly during the planning stage so there are no surprises.
Planning a House Extension in Fulham?
If you are considering a house extension in Fulham including SW6 and W6, as well as the surrounding areas of Hammersmith, Parsons Green and Putney and want to work with a team that will bring the same care, precision and pride to your home that you do, we would love to hear about your project.
We take on a select number of projects each year — chosen because we know we can do something exceptional with them. If yours sounds like one of them, get in touch and let’s find out.