A single-storey extension is a new ground-floor room built onto your house, usually at the rear or side, with its own foundations, walls and roof, creating a bigger kitchen, living space or bedroom without moving home.
From a first conversation about a single-storey extension to the day the site is cleared, homeowners in Middlesbrough deal with us directly. We come out to measure up at no cost, explain the choices in plain terms and send a written quote. For context, comparable work in Yorkshire and the Humber usually falls within £33,000–£70,000 including VAT, and it is available across TS1, TS2, TS3 and TS4.
- Guide price
- £33,000–£70,000 inc VAT
- Time on site
- 10–16 weeks on site
- Postcodes
- TS1, TS2, TS3, TS4 and TS5
- Planning rules
- England
- Local area
- North Yorkshire
- Survey
- Free, with a written quote
What should you budget for a single-storey extension in Middlesbrough?
These are guide costs, not quotes. For a single-storey extension in Middlesbrough the range is £33,000–£70,000, 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 Middlesbrough |
|---|---|---|
| Small extension (8–12m²) | A modest rear or side extension, such as a utility room or a slightly larger kitchen. | £20,500–£37,500 |
| Typical rear extension (15–25m²) | A kitchen-diner or family room with bifold doors and a rooflight or lantern. | £33,000–£70,000 |
| Large or wrap-around (30m² plus) | A wrap-around or wide rear extension, often with structural steelwork into the house. | £66,000–£122,000 |
Your price depends mostly on:
- Floor area, shape and number of corners
- Roof type, rooflights, lanterns and the amount of glazing
- Ground conditions, foundation depth and drains to divert
- Steelwork needed to open into the existing house
What do you get?
- Groundworks, foundations and below-ground drainage
- Cavity walls built and insulated to building regulations
- Flat or pitched roof, with rooflights or a lantern if specified
- Steel beams to open into the existing house
- Plastering, screed floor and internal doors
- Building control inspections and completion certificate
What are homes like around Middlesbrough?
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.
Whatever era your Middlesbrough home dates from, we plan a single-storey extension around how it is actually built rather than a one-size-fits-all specification.
Planning and building rules in Middlesbrough
The notes below cover England, which is where Middlesbrough sits. Rules change and every property is different, so we speak to the council before pricing your job.
In England, many single-storey rear extensions are permitted development: typically up to 3 m deep on a semi-detached or terraced house and 4 m on a detached house, no more than 4 m high, and covering no more than half the land around the original house. Larger rear extensions can go through the prior approval process. Side extensions, flats, listed buildings, conservation areas and homes where permitted development rights have been removed need planning permission.
Building Regulations approval is needed for almost every extension, covering foundations, structure, insulation, drainage, ventilation and fire safety. If the work is on or near a shared wall or boundary, the Party Wall etc. Act 1996 may apply.
Rules change and every property is different, so we check the planning history and constraints for your address before we quote.
The four stages
We look at the job
It starts with a survey at the property, free of charge. We check condition, access and services, ask how you want the finished result to look, and answer any questions you have about a single-storey extension.
Your fixed price
You get the price in writing, itemised so you can see where the money goes. As long as the specification stays the same, that is the price you pay for a single-storey extension.
Plan and prepare
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 single-storey extension are in place before the first day on site.
On site to finish
The work is carried out to the agreed specification, with floors and furniture protected and the site kept tidy. At the end we clean up, walk through the finished job with you and hand over any certificates.
How we work
Questions about a single-storey extension in Middlesbrough
How much does a single-storey extension cost?
A typical single-storey rear extension of 15–25m² costs £33,000–£70,000, built to a plastered finish ready for your kitchen and decoration. As a guide, allow roughly £1,600–£2,800 per square metre plus fixed costs for groundworks, steelwork and fees. Smaller extensions cost more per square metre. The kitchen, flooring and large glazed doors are usually the biggest extras. We confirm a fixed price for the agreed specification after the survey.
How long does a single-storey extension take to build?
A single-storey extension usually takes 10–16 weeks on site, from digging foundations to final plastering. Bad weather, deep foundations or a complex roof can add time. Before work starts, allow several weeks for drawings, structural calculations and building control approval, and longer if planning permission is needed. We give you a stage-by-stage programme with your quote so you know what happens each week.
Do I need an architect for an extension?
You need proper drawings for an extension, but not always a full architect service. A designer or architectural technician can produce planning and building regulations drawings, and a structural engineer provides beam and foundation calculations. If you already have drawings, we price from them. If not, we can arrange the drawings and calculations as part of the project so everything is coordinated from the start.
Can you combine a single-storey extension with other work?
Yes. Because we manage several trades under one contract, we can plan a single-storey extension alongside other work on your Middlesbrough 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 in Middlesbrough?
It depends on the work, the size of the project, your property type and whether the building is listed or in a conservation area. Middlesbrough 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.
Also covering areas around Middlesbrough
Coverage for Middlesbrough spans TS1, TS2, TS3 and TS4. Close by, Billingham, Stockton-on-Tees and Thornaby-on-Tees are covered too, and the rest of our UK-wide area follows the same survey-then-quote process from start to finish.