House Extension — Fulham & South West London
Almost every Fulham terrace has a side return and a dark back-addition kitchen, which is why extending is the most common project we are asked about. These answers cover what is achievable on that specific house type.
What is a side return extension?
The side return is the narrow strip of land alongside the rear back addition of a Victorian terrace, usually one to two metres wide and almost always wasted. Filling it in widens the back of the house across its full width, turning a dark galley kitchen into a full-width family room.
Read the full answerWhat is a wrap-around extension?
A wrap-around combines a side return infill with a rear extension, so the new space wraps around the back addition in an L shape. It is the largest single-storey extension possible on a Victorian terrace, typically adding 25 to 35m² and costing £85,000 to £140,000.
Read the full answerCan you extend a Victorian terrace?
Yes — Victorian terraces are among the most straightforward houses to extend, because the side return and shallow rear plan leave obvious room to build. The usual constraints are the 50 percent curtilage rule, conservation area status, and party wall agreements with neighbours on both sides.
Read the full answerIs a 2m extension worth it?
On a Victorian terrace, often yes — but not for the floor area. A 2m rear extension combined with a side return infill squares off the ground floor, and it is that change in shape, plus the light from a glazed roof, that transforms the space rather than the 2m itself.
Read the full answerHow long does a house extension take?
Fourteen to twenty weeks on site for a single-storey rear or side-return extension. Add eight to twelve weeks beforehand for design, structural calculations and planning, plus two months for party wall notices — so nine to twelve months from first conversation to finished room.
Read the full answerDo I need an architect for an extension?
Not legally, but you need someone competent to produce drawings and a structural engineer for the calculations. For a straightforward side return, a design-and-build contractor or architectural technologist is usually sufficient; for anything architecturally ambitious or in a conservation area, an architect earns their fee.
Read the full answerHow much value does an extension add?
A well-built single-storey extension typically adds 5 to 15 percent to a property's value in Fulham. The return is strongest where it creates a genuinely better plan — a full-width kitchen-dining space — rather than simply adding floor area to an already awkward layout.
Read the full answerWhat is the difference between single-storey and double-storey extension cost?
A double-storey extension costs less per square metre than a single-storey one — typically £2,800 to £4,000 against £3,000 to £4,500 — because the foundations, roof and groundwork are shared across two floors. The total is higher, but the cost per square metre is lower.
Read the full answerThinking about a project?
Tell us what you have in mind and we will come back with an honest view on cost, timescale and what is achievable at your address.