Two-storey extensions in Brentford
Need more room in Brentford? Two-storey and first-floor extensions add bedrooms and living space without moving. Here's everything we offer locally.
Brentford at a glance
- Postcode districts
- TW8
- Area
- Greater London, England
- Price region
- London
- Nearest towns
- Kew (0.9 miles), Ealing Common (1.5 miles), Isleworth (1.7 miles), Richmond (1.7 miles)
- Approvals
- Two-storey rear: up to 3 m deep and 7 m from the rear boundary under permitted development. Side, wraparound and front: planning permission.
Around Brentford we also work in Kew, Ealing Common and Isleworth, and across the rest of Greater London. Postcode district in and near Brentford: TW8.
Extensions available in Brentford
Two-storey rear extensions
For homes in Brentford: typical guide from £67,000.
Learn more
Two-storey side extensions
For homes in Brentford: typical guide from £103,500.
Learn more
Two-storey wraparound extensions
Our London guide starts at £144,500 for this type.
Learn more
Part single, part two-storey extensions
From £86,500 in Brentford. Free visit to firm it up.
Learn more
Extensions over a garage
From £38,000 in Brentford. Free visit to firm it up.
Learn more
First-floor extensions
Design, approvals and build for Brentford homes. Guide from £30,000.
Learn more
Two-storey extensions for semi-detached houses
Design, approvals and build for Brentford homes. Guide from £67,000.
Learn more
Two-storey extensions for detached houses
Design, approvals and build for Brentford homes. Guide from £103,500.
Learn more
Kitchen extensions with bedrooms above
For homes in Brentford: typical guide from £67,000 (before kitchen units).
Learn more
Extra bedroom and en-suite extensions
For homes in Brentford: typical guide from £67,000 (plus en-suite).
Learn moreWhich type suits your house?
Rear and side extensions suit most semi-detached and detached houses with room around them. Terraced and town-centre homes can take a two-storey extension too, with more care over neighbours, light and access.
Also available in Greater London
- Two-storey front extensions
- Two-storey extensions for end-of-terrace houses
- Two-storey annexe extensions
- Garage conversions with a room above
- Two-storey extension plans and drawings
- Planning permission for two-storey extensions
- Structural engineering for two-storey extensions
- Building regulations for two-storey extensions
- Party wall notices for extensions
- Design and build two-storey extensions
Rules for Brentford
Brentford is in England. Two-storey rear: up to 3 m deep and 7 m from the rear boundary under permitted development. Side, wraparound and front: planning permission. Householder planning application: £548 (or £575 for applications made from 8 December 2026). Lawful development certificate: £274 (about £288 for applications from 8 December 2026). Councils should decide householder applications within 8 weeks of validation.
The full England rules explained
Questions about extensions in Brentford
Do you cover Brentford?
Yes. We cover Brentford (TW8) and the surrounding area, including Kew and Ealing Common. The first site visit is free.
What does a two-storey extension cost in Brentford?
Using our London guide, a two-storey rear extension with a 4 m × 3.5 m footprint on two floors (28 m² of new floor space) is about £67,000–£90,500 including VAT. An extension over a garage is about £38,000–£55,000.
Which other places near Brentford do you cover?
Everywhere around it, including Kew (0.9 miles), Ealing Common (1.5 miles) and Isleworth (1.7 miles), and the rest of Greater London.