Loft Conversion Cost: Complete Breakdown 2026 in Poole
A loft conversion is one of the best-value home improvements — it adds a bedroom and bathroom without losing garden space. Costs range from £30,000 for a simple Velux conversion to £90,000 for a full mansard, depending on the type and specification. Here is what Poole homeowners should expect to pay.
Local cost range — Poole
£40,000–£75,000
What affects costs in Poole
Poole's 1930s semis are ideal for hip-to-gable conversions. Sandbanks properties often opt for premium mansard conversions to maximise views.
Cost estimator
Rates for Poole
6m × 4m = 24m²
Estimated cost in Poole
Excl. VAT (£10373 – £16376)
Local insight: Poole's mix of Sandbanks premium properties and Parkstone family homes means costs vary significantly. Waterfront properties command premium build rates due to access constraints and material specifications.
Cost breakdown
Cost by conversion type
Velux/rooflight: £30,000–£45,000 (simplest, no structural roof changes). Rear dormer: £40,000–£60,000 (most popular, adds headroom). L-shaped dormer: £50,000–£70,000 (two dormers meeting at a corner). Hip-to-gable + dormer: £55,000–£75,000 (maximises space on hipped roofs). Mansard: £65,000–£90,000 (most complex, most space).
What drives the cost
The main cost factors are: (1) type of conversion (dormer/mansard cost more than Velux); (2) size (one room or two); (3) en-suite bathroom (adds £5,000–£10,000); (4) staircase complexity (over the existing stair is cheapest); (5) access difficulty (scaffolding costs vary).
Professional fees for loft conversions
Design starts with the Layout Ideas Pack, done remotely or in person (subject to coverage). Structural calculations (always needed for floor joists and any roof steels), the planning application, and Building Regulations drawings are priced after that. The council also charges a planning application fee if one is required, set nationally and revised each year — the Planning Portal lists the current fees. Building control fees are separate.
| Type | Build Cost | Estimated Total |
|---|---|---|
| Velux/rooflight | £30,000–£45,000 | £35,000–£55,000 |
| Rear dormer | £40,000–£60,000 | £48,000–£72,000 |
| L-shaped dormer | £50,000–£70,000 | £58,000–£82,000 |
| Hip-to-gable + dormer | £55,000–£75,000 | £63,000–£88,000 |
| Mansard | £65,000–£90,000 | £75,000–£105,000 |
National guide figures. Local rates in Poole: £40,000–£75,000.
Frequently asked questions
National guide
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