A loft conversion turns unused roof space into a habitable room such as a bedroom, bathroom or office, with a proper staircase, insulation, fire protection and natural light from rooflights or a dormer.
Weymouth sits within our coverage for a loft conversion, as do neighbouring Poole, Yeovil and Bournemouth. Before giving a price we want to see the property: the condition of what's there now, the access, and anything that might need extra work. The guide range for the South West is £30,500–£66,000 including VAT, and your written quote will spell out exactly what that covers.
- Guide price
- £30,500–£66,000 inc VAT
- Time on site
- 6–10 weeks on site
- Postcodes
- DT3 and DT4
- Planning rules
- England
- Local area
- Dorset
- Survey
- Free, with a written quote
How much does a loft conversion cost in Weymouth?
No two jobs cost exactly the same, but the ranges below give a fair picture of a loft conversion in Weymouth. Pricing for the South West runs about 2% above the national guide, and the overall guide is £30,500–£66,000 with VAT included. We'll confirm your figure after surveying the property for free.
| Type of job | What it usually involves | Guide in Weymouth |
|---|---|---|
| Rooflight conversion | Rooflights in the existing slope, a new floor, staircase and insulation, where head height already works. | £20,500–£35,500 |
| Dormer conversion | A rear dormer adding headroom and floor space, often with a bedroom and shower room. | £32,500–£61,000 |
| Hip-to-gable or mansard | Larger structural changes to the roof for the maximum usable space. | £51,000–£87,000 |
Your price depends mostly on:
- Floor area, existing head height and roof structure
- Steelwork and any strengthening of walls below
- Adding a shower room or en-suite in the roof
- Staircase layout, fire doors and the level of finishes
What do you get?
- Structural calculations and steel beams where needed
- Dormer, hip-to-gable or rooflight structure as agreed
- Staircase designed to fit your landing and meet regulations
- Insulation to walls, roof slope and floor
- Fire doors, mains-linked smoke alarms and a protected escape route
- Plastering, internal doors and building control sign-off
What are homes like around Weymouth?
Dorset's older villages use Purbeck and Portland stone, chalk and flint, and thatch on cob or brick cottages. Bournemouth and Poole have Victorian and Edwardian villas, large interwar suburbs and plenty of bungalows and flats, while Weymouth, Dorchester and Bridport mix Georgian and Victorian streets with newer estates.
Salt spray and south-westerly winds affect coastal homes, so external finishes and fixings need to cope with marine exposure.
Knowing the typical building types in Dorset helps, but a survey of your own home in Weymouth is what decides the right approach to a loft conversion.
Permissions for a loft conversion in Weymouth
As Weymouth is in England, read the following with that system of planning and building control in mind. We check what applies to your house with the council before you receive a quote.
In England, many loft conversions are permitted development: up to 40 m³ of extra roof space on a terraced house and 50 m³ on a semi-detached or detached house, no dormer on the front roof slope facing a road, nothing higher than the existing roof, and similar-looking materials. Conservation areas, listed buildings and flats need planning permission.
Building Regulations approval is always needed for a loft conversion: floor strength, a proper staircase, insulation, fire-protected escape route and smoke alarms. The Party Wall etc. Act 1996 usually applies on attached houses.
Rules change and every property is different, so we check the planning history and constraints for your address before we quote.
How does the job run?
Survey and measure
We begin by looking at the job in person. During the free survey we discuss options, materials and budget for a loft conversion, and photograph or measure anything the quote needs to reflect.
Written quote
We put everything into a written, fixed-price quote: the specification, what's excluded, staged payments and the expected time on site. Take whatever time you need to decide; there's no pressure to commit.
Getting ready
Preparation matters as much as the build. We agree access, parking and working hours with you, order materials in good time, and confirm any permissions so the job isn't held up once it starts.
Finish and handover
On site, the agreed plan is followed and any change is put in writing first. At completion we do a final clean, go through the snagging list with you and leave you with the relevant documents.
What you can expect from us
Common questions
What fire safety measures does a loft conversion need?
A loft conversion needs a safe way out in a fire, because the new room is high above the ground. This usually means a protected stair route down to an exit, with fire doors onto the stairway, mains-linked smoke alarms on each floor and sometimes an escape window. The exact approach depends on your house layout. Building control checks these measures before signing off the work.
What happens at the survey?
We visit your home at a time that suits you, look at the area involved, take measurements and check access, condition and any services that might be affected. We talk through what you want from a loft conversion, explain the options and answer questions. There is no charge and no obligation; afterwards we send a written quote.
Can I put a bathroom in my loft?
A bathroom or shower room can usually be added in a loft conversion if waste pipes can reach the soil stack with enough fall, or a pumped system can be used. Dormers make this easier because they give standing height for a shower. Water pressure, extraction and the position of the boiler also matter. We plan the bathroom layout at the design stage so pipes are hidden in the structure.
Can you combine a loft conversion with other work?
Yes. Because we manage several trades under one contract, we can plan a loft conversion alongside other work on your Weymouth home, such as new windows with rendering, or a kitchen refit with an extension. Combining jobs can reduce repeat set-up such as scaffolding, skips and access, and every element is listed and priced in the same written quote.
Do I need planning permission for a loft conversion?
Whether a loft conversion needs planning permission depends on its size and design, your home's location, whether it is listed or in a conservation area, and which UK nation you live in. In England, many conversions fall under permitted development if the added volume is within 40m³ for terraced houses or 50m³ for other houses and nothing extends beyond the front roof slope. We check what applies before quoting.
Nearby towns
Our coverage in Weymouth includes DT3 and DT4. We also travel to Poole, Yeovil and Bournemouth, so neighbouring addresses are looked after on exactly the same terms as those in town.

