With house prices in Bournemouth still running high, more and more homeowners are choosing to extend upwards rather than move. A loft conversion gives you an extra bedroom, a home office, or even a self-contained space — without the estate agent fees, stamp duty, and stress of buying somewhere bigger.
But the number one question we get asked is: “How much is it actually going to cost?” And the honest answer is: it depends. But we can give you real numbers.
The Honest Answer: Loft Conversion Cost Ranges in Bournemouth
There’s no single price for a loft conversion, but here’s a realistic guide based on what we’ve quoted and built in the Bournemouth area:
| Conversion Type | Typical Price Range | Notes |
|---|---|---|
| Velux / Rooflight Conversion | £20,000 – £28,000 | The most affordable option. No structural changes to the roof shape — just skylights added into the existing roof. Best for lofts with enough headroom already. |
| Dormer Conversion | £28,000 – £42,000 | The most popular choice. A box-shaped extension to the roof slope gives you full standing height and much more usable floor space. Almost always includes a bathroom. |
| Hip-to-Gable Conversion | £32,000 – £48,000 | Common in Bournemouth’s semi-detached homes. The sloping hip end of the roof is replaced with a vertical gable wall, dramatically increasing the floor area. |
| Mansard Conversion | £45,000 – £65,000+ | The highest-spec option, common in period properties. Nearly vertical rear wall with a flat or very shallow pitch roof. Maximum space, maximum cost. |
“These aren’t figures we’ve pulled from thin air — they’re based on actual projects we’ve completed in Bournemouth, Poole and Christchurch over the past five years.” — Mike McMann, MNM Building Services
What Drives the Cost Up or Down
Several factors will push your quote higher or lower than the average:
Size of the loft — larger floor area means more materials, more labour, more time. A standard semi will cost less than a large detached with a complex roof shape.
Structural work required — if your existing floor joists can’t support a habitable room, they’ll need to be reinforced. This adds cost but is non-negotiable for safety.
Access and staircase — a new staircase needs to be planned carefully. In older Bournemouth terraces, finding space for the stairwell without losing a bedroom below is often the trickiest part of the job.
Finish level — a basic loft conversion (plastered, no ensuite, standard windows) costs significantly less than one with a full ensuite bathroom, bespoke storage, and high-spec glazing.
Planning permission — most loft conversions fall under Permitted Development in Bournemouth, but homes in conservation areas or with specific roof profiles may need full planning. Budget extra time and potentially some architect fees if that applies to you.
Red Flags When Getting Quotes
We’ve heard too many stories from homeowners who went with the cheapest quote and regretted it. Watch out for:
- No site visit before quoting Any builder who quotes without seeing your loft is guessing. Materials, structural requirements, and access issues are impossible to assess remotely.
- Vague or verbal quotes Your quote should be a written document, broken down by work stage. If someone gives you a round number on the phone, that’s not a quote.
- Unusually low prices A fully compliant, structurally sound, plastered dormer conversion in Bournemouth cannot be done professionally for £12,000. If you’re seeing prices that feel too good, they usually are.
- Requests for large deposits upfront A reasonable deposit is normal. 50%+ before any work starts is a red flag.
Why MNM Always Visits Before We Quote
We never price a loft conversion without standing in your loft first. Access matters. Joist sizes matter. Roof pitch matters. The position of the party wall matters.
Our free estimates take around 45–60 minutes. We’ll walk you through what’s feasible, what it’ll cost at each specification level, and give you a written quote you can hold us to.
We work across Bournemouth, Poole, Christchurch, and the surrounding areas. All our work is covered by public liability insurance, and we’re listed on Checkatrade with a 10-star rating.