Side Extensions in South Wales

A side extension uses space that's otherwise wasted — the narrow side passage of a Victorian terrace, the gap next to a semi-detached, or a redundant driveway. Side-return extensions in particular transform cramped Victorian kitchens by widening them by 1–2m. We deliver a full design-and-build with premium glazing as standard. Most side extensions complete in 10–16 weeks.

Benefits

  • Use Wasted Space: Side passages and narrow driveways are often the highest-value square footage you can build on.
  • Transforms Victorian Kitchens: Side-return extensions widen narrow Victorian kitchens by 1–2m — game-changing.
  • Design-and-Build Service: Architect, structural engineer, Building Regs and the build — all in-house.
  • Premium Glazing Included: Roof lanterns, skylights and bifold doors built into the original quote.
  • Adds Major Value: Side-return kitchen extensions consistently deliver some of the best ROI in residential property.
  • Fixed Written Quote: Itemised stage-payment pricing — no open-ended invoices.

Our side extensions range

  • Side-Return Extension: Fill in the narrow side passage of a Victorian/Edwardian terrace to widen the kitchen.
  • Single-Storey Side Extension: Single-storey build next to a semi or detached house — extra lounge, dining or utility.
  • Double-Storey Side Extension: Two floors of new space — bigger living downstairs, extra bedroom + bathroom upstairs.
  • Side Extension with Lantern: Side extension topped with a roof lantern or skylights for maximum natural light.

Frequently Asked Questions

Do I need planning permission for a side extension?

Single-storey side extensions can sometimes fall under permitted development, but most side extensions — especially two-storey or wider than half the original house width — need planning. We confirm before quoting.

How long does a side extension take?

Single-storey side extensions typically complete in 10–14 weeks. Side-returns are usually 10–12 weeks.

How much does a side extension cost?

Typically £1,900–£2,900 per m² depending on glazing and finish. A typical 12 m² Victorian side-return is usually £28,000–£42,000. 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.