House Extensions in South Wales

Fairway delivers full design-and-build house extensions across South Wales and the Bristol area — from compact single-storey rear builds to large wrap-around kitchen extensions and two-storey side builds. We handle everything in-house: architect drawings, structural engineer calcs, planning submissions, Building Control, the build itself and all the glazing. One team, one trusted point of contact, fixed written quotes.

Benefits

  • Full Design-and-Build: Architect, structural engineer, Building Regs and the build — all under one roof.
  • Fixed Written Quote: Detailed itemised pricing with stage payments — no open-ended invoices.
  • Premium Glazing Standard: Aluminium bifolds, sliders and lanterns built into the original quote — never an upsell.
  • Planning Handled: We prepare drawings, submit applications, manage conditions and Building Control sign-off.
  • 10-Year Workmanship Guarantee: Backed by our long-standing local installer reputation.
  • Beat-Any-Like-For-Like Quote: Bring us a matching written quote and we'll beat it — guaranteed.

Our house extensions range

  • Single-Storey House Extension: Rear, side or wrap-around — typically 15–35 m² of new ground-floor space.
  • Double-Storey House Extension: Two floors of new space — extra bedroom + en-suite over a bigger living room.
  • Kitchen House Extension: Open-plan kitchen-diner extension with bifolds and roof lantern as standard.
  • Garage Extension Knock-Through: Combine a garage conversion with a new extension for maximum new floorspace.

Frequently Asked Questions

Do you handle the architect drawings and planning?

Yes — we provide a full design-and-build service including architect drawings, structural calcs, planning applications and Building Control sign-off.

How long does a house extension take?

Single-storey extensions typically complete in 8–14 weeks. Double-storey and wrap-arounds run 14–22 weeks. We provide a written programme with the quote.

How much does a house extension cost?

Single-storey runs £1,800–£2,800 per m². Double-storey runs £2,200–£3,200 per m² of new floor area. Wrap-arounds typically £75,000–£140,000. Fixed quotes after survey.

Free Quote in 24 Hours — We Beat Any Like-for-Like Quote

Get a fixed-price quote within 24 hours. Free home survey. 10-year guarantee. Call 02920 860894 or request a callback.