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.
Whatever type of house you own in Bishop Auckland, we start by looking at how a single-storey extension would fit it rather than offering a standard package. We cover DL4 and DL14 and neighbouring places such as Newton Aycliffe, Durham and Darlington. One named person looks after you from survey to handover, and nothing is booked until you hold our figure in writing, fixed for the work described.
- Guide price
- £31,500–£68,000 inc VAT
- Time on site
- 10–16 weeks on site
- Postcodes
- DL4 and DL14
- Planning rules
- England
- Local area
- County Durham
- Survey
- Free, with a written quote
What should you budget for a single-storey extension in Bishop Auckland?
Here is how the guide price for a single-storey extension breaks down in Bishop Auckland. We start from national figures and adjust for the North East, which comes out about 10% below the national guide. The resulting range, VAT included, is £31,500–£68,000, and a survey, at no cost to you, firms it up.
| Type of job | What it usually involves | Guide in Bishop Auckland |
|---|---|---|
| Small extension (8–12m²) | A modest rear or side extension, such as a utility room or a slightly larger kitchen. | £20,000–£36,000 |
| Typical rear extension (15–25m²) | A kitchen-diner or family room with bifold doors and a rooflight or lantern. | £31,500–£68,000 |
| Large or wrap-around (30m² plus) | A wrap-around or wide rear extension, often with structural steelwork into the house. | £63,000–£117,000 |
Expect these to shape the final quote:
- 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
Scope of the work
- Cavity walls built and insulated to building regulations
- Steel beams to open into the existing house
- Electrics and plumbing by qualified trades, with certificates
- Windows and external doors, including bifolds if chosen
- Plastering, screed floor and internal doors
- Building control inspections and completion certificate
Building in Bishop Auckland
Colliery villages across County Durham are lined with brick and stone terraces, many built for mining families. Durham City has Georgian and Victorian streets, Darlington has Victorian terraces and villas, and Peterlee and Newton Aycliffe were planned as post-war new towns. Dales farmhouses in Weardale and Teesdale are stone, often under stone or slate roofs.
Colliery terraces commonly suit loft rooms, rear extensions and window replacement, and many need repointing. New-town homes often benefit from rendering or cladding upgrades and roofline renewal, while stone farmhouses may need lime work.
In Bishop Auckland, as elsewhere in County Durham, we take the building's age and construction into account before recommending anything, because both can change what is involved in a single-storey extension.
Permissions for a single-storey extension in Bishop Auckland
Homes in Bishop Auckland come under the regulations for England, summarised below. We don't rely on general rules alone: we confirm the position for your address with the council before a quote goes out.
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.
How does the job run?
A visit to your home
A free survey comes first. It gives us what we need to price a single-storey extension properly, including dimensions, existing materials and access for deliveries, and gives you the chance to ask anything you like.
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
Before anyone starts, we confirm the programme in writing, check whether consents are required and arrange deliveries. If a skip or scaffolding on the road needs a permit, we apply for it.
Finish and handover
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.
Why homeowners choose us
Questions about a single-storey extension in Bishop Auckland
Is a flat roof or a pitched roof better on an extension?
A flat roof is quicker to build and usually costs less, gives a clean modern look and works well with a roof lantern. A pitched roof matches the main house, sheds water faster and allows a vaulted ceiling, but it costs more and its height can affect neighbours. Modern flat roofs in EPDM rubber or GRP last well when properly detailed. Planning rules on height can also decide the choice.
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.
Is the price fixed?
Yes, for the specification we agree. Your written quote sets out exactly what is included at a fixed price. It only changes if you ask for something different, or if a problem the survey could not reasonably reveal later needs extra work. In either case we explain the change and confirm it in writing before going ahead.
Can we stay at home during the build?
Most people stay at home while we build a single-storey extension, because the new structure goes up outside before we break through. The disruptive part is usually the last few weeks, when we open into the house and fit the kitchen. We put up dust screens, keep a safe route through the house and agree a temporary kitchen setup if needed. Water and power are only off for short, planned periods.
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.
Nearby towns
If your address falls within DL4 and DL14, we cover it. The same goes for neighbouring Newton Aycliffe, Durham and Darlington, which we include alongside Bishop Auckland when arranging surveys and quotes.

