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.
In New Malden, as anywhere in London, the price of a loft conversion is driven mainly by size, materials and access. Across London our guide sits at £39,000–£84,000 with VAT, but restricted parking, a narrow side passage or extra preparation can move the figure either way. That is why every price we give follows a visit to the house.
- Guide price
- £39,000–£84,000 inc VAT
- Time on site
- 6–10 weeks on site
- Postcodes
- KT1, KT2, KT3, KT4 and KT5
- Planning rules
- England
- Local area
- Greater London
- Survey
- Free, with a written quote
Loft conversions prices in New Malden
The costs listed here are typical for a loft conversion around New Malden and include VAT. They reflect labour and material costs in London, about 30% above the national guide, giving a range of £39,000–£84,000. Exact pricing depends on your home, so we only fix it once a free site survey is done.
| Type of job | What it usually involves | Guide in New Malden |
|---|---|---|
| Rooflight conversion | Rooflights in the existing slope, a new floor, staircase and insulation, where head height already works. | £26,000–£45,500 |
| Dormer conversion | A rear dormer adding headroom and floor space, often with a bedroom and shower room. | £41,500–£78,000 |
| Hip-to-gable or mansard | Larger structural changes to the roof for the maximum usable space. | £65,000–£110,000 |
What moves the price up or down:
- Conversion type: rooflight, dormer, hip-to-gable or mansard
- Floor area, existing head height and roof structure
- Adding a shower room or en-suite in the roof
- Staircase layout, fire doors and the level of finishes
Scope of the work
- 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
- Fire doors, mains-linked smoke alarms and a protected escape route
- Electrics, heating and plumbing by qualified trades, with certificates
- Plastering, internal doors and building control sign-off
Homes in London
London's housing is dominated by Victorian and Edwardian terraces, often in yellow London stock brick, with Georgian terraces in central districts and mansion blocks across many inner areas. Outer boroughs have large belts of interwar semis, and there are extensive post-war council estates. Many houses have been split into flats, and conservation areas are widespread.
Terraces suit side-return extensions and rear dormer loft conversions; interwar semis commonly take hip-to-gable lofts. Shared party walls, restricted parking and conservation rules often shape the plans and the programme.
With that background in mind, here is how we typically handle a loft conversion for homes in New Malden, from the first visit to the finished result.
Permissions for a loft conversion in New Malden
Each UK nation sets its own consent rules, and New Malden is in England. What follows is a plain summary; we check the specifics for your property with the council before pricing anything.
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.
What happens after you get in touch?
A visit to your home
Book a visit and we'll come to you. The survey covers measurements, the state of what's there now and any obvious constraints, so the price that follows is based on your actual home, not an average.
Price and scope agreed
The quote arrives in writing, not over the phone. It covers the full scope, the finishes you've chosen, any exclusions and the payment schedule, with a fixed price tied to that specification.
Booking the work
Next comes planning the work itself. We set a start date that suits you, line up the right trades, and make sure any approvals for a loft conversion are in place before the first day on site.
On site to finish
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.
How we work
Frequently asked questions
Do I need planning permission in New Malden?
It depends on the work, the size of the project, your property type and whether the building is listed or in a conservation area. New Malden is in England, so England's rules apply. Many smaller jobs need no planning application, but some still need building control approval. We check what applies to your address before quoting.
Is my loft suitable for conversion?
A loft is usually suitable for conversion if there is enough head height, a roof structure that can be adapted and space for a staircase. A common rule of thumb is at least 2.2m from the top of the ceiling joists to the underside of the ridge, though dormers and mansards can create height where it is short. Modern trussed roofs need more structural work. We check all of this at the survey.
Who do I deal with during the job?
One point of contact manages your project from survey to handover. They schedule the trades working under our contract, keep you updated on progress, and are the person to call with any question. You don't need to coordinate builders, electricians or decorators separately, because that is part of what we do.
Can we stay at home during a loft conversion?
Most people stay at home during a loft conversion, because much of the work happens from scaffolding outside and the roof is opened up from above. The most disruptive point is near the end, when we break through the ceiling to fit the new staircase, which usually takes a few days. We put up dust screens on the landing and plan noisy work for reasonable hours.
Where will the new staircase go?
The new staircase usually sits above the existing stairs, rising from the landing so it uses space that is already circulation. Sometimes it needs to come from a small bedroom or box room, which reduces that room's size. Building regulations set rules on headroom, step size and handrails, with some flexibility for lofts. We look at options at the survey and show you how each affects the floor below.
Also covering areas around New Malden
From KT1, KT2, KT3 and KT4 to the edges of New Malden and on into Surbiton, Morden and Wimbledon, we can arrange a site visit and a written quote for your project, planned around dates that work for you.