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.
We offer a loft conversion across North Yorkshire, and Thornaby-on-Tees is one of the places we cover, along with nearby Stockton-on-Tees, Yarm and Billingham. Before anything is agreed we visit, check the existing structure and talk through your options. You then receive a written quote setting out the full scope; for most homes in Yorkshire and the Humber it sits within £28,000–£61,000 including VAT.
- Guide price
- £28,000–£61,000 inc VAT
- Time on site
- 6–10 weeks on site
- Postcodes
- TS5, TS16, TS17 and TS18
- Planning rules
- England
- Local area
- Stockton-on-Tees
- Survey
- Free, with a written quote
Loft conversions prices in Thornaby-on-Tees
These are guide costs, not quotes. For a loft conversion in Thornaby-on-Tees the range is £28,000–£61,000, VAT included, reflecting prices in Yorkshire and the Humber that are about 6% below the national guide. Once we have visited for a free survey, you get a firm figure for the scope you approve.
| Type of job | What it usually involves | Guide in Thornaby-on-Tees |
|---|---|---|
| Rooflight conversion | Rooflights in the existing slope, a new floor, staircase and insulation, where head height already works. | £19,000–£33,000 |
| Dormer conversion | A rear dormer adding headroom and floor space, often with a bedroom and shower room. | £30,000–£56,000 |
| Hip-to-gable or mansard | Larger structural changes to the roof for the maximum usable space. | £47,000–£80,000 |
The main things that change the figure:
- Conversion type: rooflight, dormer, hip-to-gable or mansard
- 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
- 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
Local housing and a loft conversion
York has medieval timber-framed, Georgian and Victorian buildings, Harrogate has stone Victorian villas and terraces, and the Dales and Moors are built of limestone and sandstone, often under stone-slate or pantile roofs. Teesside towns within the county, such as Middlesbrough and Redcar, have Victorian red-brick terraces and post-war estates.
Dales and Moors properties often need lime pointing, roof repairs and window designs acceptable within a national park. Teesside brick terraces suit loft rooms and rear extensions, and estate homes commonly take garage conversions.
With that background in mind, here is how we typically handle a loft conversion for homes in Thornaby-on-Tees, from the first visit to the finished result.
Do you need permission in Thornaby-on-Tees?
Because Thornaby-on-Tees falls under England's rules, the guidance below is the version relevant to you. Before sending a price, we check your property's position with the council.
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 arrange a free site survey on a date convenient to you. We measure up, look at the existing structure and access, and discuss your plans for a loft conversion so the price reflects your home.
Your fixed price
We turn the survey notes into a written quote. The price is fixed for the specification we agree, and the document sets out materials, scope and payment stages in plain language.
Plan and prepare
With the quote agreed, we book the work in and handle preparation: permissions where needed, building control notifications, material orders and access arrangements for your Thornaby-on-Tees property.
The work itself
Work goes ahead as scheduled and you deal with one contact throughout. When the last trade leaves, we clear and clean the site, talk you through what has been done and pass on any certificates and care instructions.
Why homeowners choose us
Loft conversions in Thornaby-on-Tees: questions
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.
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.
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.
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.
Near Thornaby-on-Tees
Live in Thornaby-on-Tees? Our coverage takes in the TS5, TS16, TS17 and TS18 postcode areas and reaches out to Stockton-on-Tees, Yarm and Billingham, so homes on the outskirts and in the next town along are included.

