Extension Cost Per Square Metre 2026: What to Expect in Bournemouth
Cost per square metre is the standard way to compare extension quotes. But the figure varies dramatically depending on specification, region, complexity, and what is included. Here is what Bournemouth homeowners should expect to pay.
Local cost range — Bournemouth
£1,800–£2,600/m²
What affects costs in Bournemouth
Bournemouth build rates are at the Dorset average. The tight access on terraced streets can add 5–10% compared to detached properties with easy access.
Cost estimator
Rates for Bournemouth
6m × 4m = 24m²
Estimated cost in Bournemouth
Excl. VAT (£10373 – £15272)
Local insight: Bournemouth's Victorian terraces often need party wall agreements on both sides, adding £1,400–£3,000 to the total. Side-return extensions on terraces are the most common project here.
Cost breakdown
2026 rates by specification
Basic specification (standard bricks, flat roof, basic windows): £1,500–£2,000/m². Standard specification (quality bricks, bi-fold doors, underfloor heating): £2,000–£2,800/m². Premium specification (bespoke materials, structural glazing, high-end finishes): £2,800–£3,500/m². These are Dorset rates.
What affects the rate
Foundation depth (clay soil or trees nearby = deeper = more expensive), access difficulty (narrow lanes or terraced properties), specification level, bathroom inclusion (wet rooms cost more per m²), and the builder's current availability. A busy builder quotes higher.
| Region | Standard | High Spec |
|---|---|---|
| Dorset | £1,800–£2,200 | £2,500–£3,200 |
| London | £2,500–£3,500 | £3,500–£5,000 |
| South East | £2,000–£2,800 | £2,800–£3,800 |
| Midlands | £1,600–£2,200 | £2,200–£3,000 |
| North | £1,400–£2,000 | £2,000–£2,800 |
National guide figures. Local rates in Bournemouth: £1,800–£2,600/m².
Frequently asked questions
National guide
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