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.
Cost is usually the first question about a single-storey extension, so here is the guide for the West Midlands: £34,500–£74,000 including VAT. We cover the whole of West Midlands, with Birmingham, Coventry, Wolverhampton and Dudley among the main centres. Because each UK nation sets its own rules, we check the requirements in England for your property, then put a firm price on paper following a free survey.
- Guide price
- £34,500–£74,000 inc VAT
- Time on site
- 10–16 weeks on site
- Planning rules
- England
- Price level
- About 2% below the national guide
- Towns listed
- 24
- Survey
- Free, with a written quote
Single-storey extensions prices in West Midlands
Every figure below is a guide for a single-storey extension in West Midlands, inclusive of VAT. Regional pricing for the West Midlands works out about 2% below the national guide, and the overall span is £34,500–£74,000. The survey costs you nothing, and after it we commit to a firm price for your specification in writing.
| Type of job | What it usually involves | Guide in West Midlands |
|---|---|---|
| Small extension (8–12m²) | A modest rear or side extension, such as a utility room or a slightly larger kitchen. | £21,500–£39,000 |
| Typical rear extension (15–25m²) | A kitchen-diner or family room with bifold doors and a rooflight or lantern. | £34,500–£74,000 |
| Large or wrap-around (30m² plus) | A wrap-around or wide rear extension, often with structural steelwork into the house. | £69,000–£127,000 |
The main things that change the figure:
- 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
- Finishes, kitchen, flooring and heating specification
What’s included?
- Groundworks, foundations and below-ground drainage
- Flat or pitched roof, with rooflights or a lantern if specified
- Steel beams to open into the existing house
- Electrics and plumbing by qualified trades, with certificates
- Windows and external doors, including bifolds if chosen
- Building control inspections and completion certificate
Homes in West Midlands
Red-brick Victorian and Edwardian terraces are common in the inner areas of Birmingham, Wolverhampton and the Black Country, ringed by large swathes of 1930s semis with bay windows and hipped roofs. You'll also find post-war council estates, some system-built blocks, Coventry's rebuilt centre and larger detached homes in Solihull and Sutton Coldfield.
1930s semis often suit side and rear extensions, hip-to-gable loft conversions and garage conversions. Victorian terraces tend to need repointing, roof work and replacement windows, and many have room for a side-return extension.
An inland climate with regular winter frosts means freeze-thaw damage to soft brick and old mortar is a common reason for repointing and render repairs.
Do you need permission in West Midlands?
England, Wales, Scotland and Northern Ireland each handle planning a little differently. West Midlands comes under England, covered below, and we raise any questions with the council before your quote is finalised.
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?
Survey and measure
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.
Getting ready
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
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.
What you can expect from us
Questions about a single-storey extension in West Midlands
How much will a single-storey extension cost in West Midlands?
As a guide, expect to pay £34,500–£74,000 including VAT for a single-storey extension in West Midlands. That range is adjusted for the West Midlands, which runs about 2% below 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 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.
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.
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.
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 West Midlands 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.
Towns in West Midlands
Find your town below. Every place listed in West Midlands is covered for a single-storey extension, with the same survey, written quote and fixed-price process.

