
Many Victorian and Edwardian terraced houses in London have a rear outrigger with a narrow passage, the side return, running alongside it. A side-return extension fills that passage so the kitchen or living space can be much wider, often creating a single open room across the back of the house.
Side-return, rear or wrap-around?
- A side-return extension fills the passage beside the outrigger.
- A rear extension adds depth at the back of the house.
- A wrap-around extension combines the two, which gives the most space but is also the biggest job.
Things to check before you commit
- Planning. Some single-storey side extensions can be built under permitted development, but there are limits on height and width, and combining a side and rear extension often goes beyond them. Flats and homes in conservation areas have different rules.
- Party walls. Building up to or onto the boundary wall, or cutting into a shared wall to fit steel beams, usually needs notices under the Party Wall etc. Act 1996.
- Drains. In London there is often a public sewer or shared drain close to the house. Building over or near it may need the water company’s agreement, which is Thames Water in most of London.
- Light. A tall boundary wall can affect a neighbour’s light, and a lower or sloping roof design is sometimes used to limit that.
- Structure. Opening up the side wall to join old and new space means steel beams, and the engineer’s design affects the build.
Getting a clear price
A good brief makes quotes comparable: drawings, a specification for glazing and finishes, and a list of what you expect to be included. Our guide to what affects the cost of a house extension explains the main variables.
This guide is general information for homes in England and is not legal or planning advice. Rules can change and differ between properties and local authorities, so always confirm the position with your council or a qualified professional.
Learn more about our extension service or request a quote for a side-return project.