Service · London
House Extensions in London
From single-storey kitchen extensions to full double-storey side-returns, we design and build extensions that add space, value and light to your London home — completed on time, on budget and to a 10-year structural guarantee.
Why Prime Build
What you get when you
work with us.
The same in-house team, the same five-stage process, the same 10-year guarantee — across every service we offer.
- 10+ years extending London homes — Wembley, Ealing, Richmond, Chiswick, Wimbledon, Hampstead, Croydon
- Full planning, party-wall & building-control management included
- Fixed-price contracts with weekly progress reports — no surprises
- In-house structural, joinery, MEP and finishing teams
- 10-year structural guarantee on every extension we build
Our process
A five-stage process built to remove surprises.
01
Discovery
Free 45-min on-site or virtual consultation to understand your goals and budget.
02
Design
Concept design with feasibility, cost engineering and 3D visuals.
03
Planning
We handle planning, party-wall agreements and building-control submission.
04
Build
Weekly reports, in-house trades, locked budget — 12–20 weeks for most extensions.
05
Handover
Snagging walk-through, warranty pack and aftercare.
Recent house extensions
Selected projects.
Extension · Ealing, W5
Ealing Two-Storey Side Extension — Completed
Extension · Ealing, W5
Ealing Rear Extension
Extension · Wembley Park, HA9
Wembley Side-Return — Structural Opening
Extension · Chiswick, W4
Chiswick Extension — External Brickwork & Soldier Course
Extension · Ealing, W5
Ealing Extension — Sandstone Patio Install
Extension · Richmond, TW10
Richmond Kitchen Extension — Finished Open-Plan Diner
Frequently asked questions
Answers about house extensions.
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