Rear and Side House Extension London and Hertfordshire
Add maximum ground floor space with a rear and side extension by LCCL Construction. We design and build combined rear and side extensions on semi-detached and detached properties across London and Hertfordshire. Full design and build from £55,000. LABC Award Winners 2024. Over 200 reviews rated 4.7 out of 5.
LABC Awards
Winners 2024
200+ Reviews
4.7 / 5 Rating
NFB Members
LABC Partners
What Is a Rear and Side Extension?
A rear and side extension combines a rear extension with a side extension to add maximum ground floor space. Unlike a wraparound extension (which infills a narrow side return), a rear and side extension extends the full side elevation of a semi-detached or detached house to create a substantially wider and deeper ground floor layout.
This type of extension is particularly suited to semi-detached and detached properties in London and Hertfordshire that have sufficient space to the side. It can add a significant amount of floor area — often 30 to 50 square metres — creating a large open-plan kitchen-diner-living area, a separate utility room, a downstairs bathroom or a ground floor bedroom.
LCCL Construction designs and builds rear and side extensions across London and Hertfordshire. Based in Finchley, London N3, we handle every stage from architectural design through to construction and completion.
How Much Does a Rear and Side Extension Cost?
Rear and side extension costs in London typically range from £55,000 to £100,000 depending on the total floor area and specification. A standard rear and side extension on a semi-detached house, adding approximately 30 to 40 square metres, typically costs £55,000 to £80,000. Larger schemes on detached properties can cost £80,000 to £100,000 or more.
Prices include full design and build. Get an instant quote at lcclconstruction.co.uk or call 020 8037 7332.
Subject final drawings, how big the area is, location, finishing, structural drawings, alteration, time when, costs subject to change.
Planning Permission
Rear and side extensions that remain within permitted development limits may not require planning permission, but the side extension element must not exceed half the width of the original house. Many rear and side schemes exceed permitted development and require a full planning application.
LCCL Construction handles all planning applications and building regulations as standard.
What Is Included?
Full design and build: consultation, measured survey, architectural design, planning, building regulations, structural calculations, party walls, all construction, electrics, plumbing, plastering, decoration, building control sign-off and optional 10-year LABC warranty.
Areas We Cover
We build rear and side extensions across London and Hertfordshire including Barnet, Finchley, Hendon, Muswell Hill, Southgate, Enfield, Edgware, Borehamwood, St Albans, Potters Bar, Bushey, Watford, Ealing, Hampstead, Highgate, Clapham, Putney, Wandsworth, Hackney, Islington and surrounding areas. Call 020 8037 7332.
Frequently Asked Questions
How much does a rear and side extension cost in London?
Rear and side extension costs in London typically range from £55,000 to £100,000 depending on the total floor area and specification. A standard scheme on a semi-detached house adding 30 to 40 square metres costs £55,000 to £80,000. Subject final drawings, how big the area is, location, finishing, structural drawings, alteration, time when, costs subject to change.
What is the difference between a wraparound and a rear and side extension?
A wraparound extension infills a narrow side return (1 to 2 metres wide) typically found on terraced houses. A rear and side extension extends the full side elevation of a semi-detached or detached house, adding a much larger amount of floor space.
Do I need planning permission for a rear and side extension?
The side extension element must not exceed half the width of the original house under permitted development. Many rear and side schemes exceed this limit and require a full planning application. LCCL Construction handles all planning applications as standard.
How much space does a rear and side extension add?
A rear and side extension can add 30 to 50 square metres of ground floor space depending on the size of the property and the extent of the side and rear projections.
How long does a rear and side extension take?
A rear and side extension typically takes 14 to 20 weeks to build. The full project timeline is usually 5 to 8 months from consultation to completion.
How do I get started?
Call us on 020 8037 7332, book a free consultation at lcclconstruction.co.uk, or get an instant quote online.