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.
Tonbridge sits within our coverage for a loft conversion, as do neighbouring Tunbridge Wells, Sevenoaks and Crowborough. 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 East is £33,500–£73,000 including VAT, and your written quote will spell out exactly what that covers.
- Guide price
- £33,500–£73,000 inc VAT
- Time on site
- 6–10 weeks on site
- Postcodes
- TN9, TN10 and TN11
- Planning rules
- England
- Local area
- Kent
- Survey
- Free, with a written quote
How much does a loft conversion cost in Tonbridge?
In Tonbridge, guide figures for a loft conversion sit at £33,500–£73,000, VAT included. We set them using rates for the South East, currently about 12% above the national guide. The table shows what pushes a project towards either end of the range; your own price is set after a free survey.
| Type of job | What it usually involves | Guide in Tonbridge |
|---|---|---|
| Rooflight conversion | Rooflights in the existing slope, a new floor, staircase and insulation, where head height already works. | £22,500–£39,000 |
| Dormer conversion | A rear dormer adding headroom and floor space, often with a bedroom and shower room. | £36,000–£67,000 |
| Hip-to-gable or mansard | Larger structural changes to the roof for the maximum usable space. | £56,000–£95,000 |
What moves the price up or down:
- Conversion type: rooflight, dormer, hip-to-gable or mansard
- Floor area, existing head height and roof structure
- Steelwork and any strengthening of walls below
- Staircase layout, fire doors and the level of finishes
What do you get?
- New floor joists strong enough for a habitable room
- 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
- Electrics, heating and plumbing by qualified trades, with certificates
- Plastering, internal doors and building control sign-off
What are homes like around Tonbridge?
Kent's older buildings include oast houses, weatherboarded cottages, Wealden timber-framed houses and Kentish ragstone walls. Medway towns have long rows of Victorian terraces, Margate and Ramsgate have Regency and Victorian seafronts, and Ashford, Maidstone and Dartford have seen large new estates alongside interwar and post-war housing.
Victorian terraces suit loft rooms and rear extensions; weatherboarded and timber-framed buildings may need cladding repairs and lime work. Newer estate homes often take garage conversions, porches and landscaping.
With that background in mind, here is how we typically handle a loft conversion for homes in Tonbridge, from the first visit to the finished result.
Do you need permission in Tonbridge?
England, Wales, Scotland and Northern Ireland each handle planning a little differently. Tonbridge comes under England, covered below, and we raise any questions with the council before your quote is finalised.
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.
The four stages
Free site survey
A free survey comes first. It gives us what we need to price a loft conversion properly, including dimensions, existing materials and access for deliveries, and gives you the chance to ask anything you like.
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
Once you accept, we agree start dates, order materials and deal with any planning, building control or neighbour notices the job needs. You'll know who is coming and when before work begins.
On site to finish
Our trades complete a loft conversion while your point of contact keeps you updated. When everything is finished, we clear the site, take away waste and go through the result with you before handover.
Working with SK Home Improvements
Loft conversions in Tonbridge: questions
How much will a loft conversion cost in Tonbridge?
As a guide, expect to pay £33,500–£73,000 including VAT for a loft conversion in Tonbridge. That range is adjusted for the South East, which runs about 12% above the national guide. Where your project lands depends on size, materials, access and the condition of what is already there. We confirm a fixed price in writing after a free survey of your home.
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.
Does the Party Wall Act apply to a loft conversion?
The Party Wall etc. Act 1996 applies in England and Wales only, and loft conversions on terraced and semi-detached houses often fall within it, because steel beams are usually set into the shared wall. You must serve notice on the neighbour before work starts, and they can agree or appoint a surveyor. Scotland and Northern Ireland have no equivalent Act. We tell you during the survey whether notices are likely.
How much does a loft conversion cost?
A typical dormer loft conversion on a 3-bed semi costs £33,500–£73,000. A simple rooflight conversion costs less, while hip-to-gable and mansard conversions cost more because they change the roof structure. As a rough guide, allow around £800–£1,700 per square metre of new floor plus fixed costs for the staircase, steels and fees. Adding a shower room is the most common extra. We confirm a fixed price after surveying your loft.
Which postcodes in Tonbridge do you cover?
We cover TN9, TN10 and TN11, along with the rest of Kent. If your postcode is not listed, get in touch anyway: our coverage is UK-wide, and we can usually arrange a survey wherever you live. Enter your postcode in the guide-price tool or contact form and we will confirm.
Nearby towns
From TN9, TN10 and TN11 to the edges of Tonbridge and on into Tunbridge Wells, Sevenoaks and Crowborough, we can arrange a site visit and a written quote for your project, planned around dates that work for you.