A double-storey extension adds two floors of new space to your house in one build, typically a larger kitchen or living room downstairs with an extra bedroom, bathroom or en-suite above, sharing one set of foundations and one roof.
Getting a double-storey extension right in Halesowen starts with understanding the house you already have: its age, how it was built and what has been altered over the years. We survey first, then commit on paper to a price that holds as long as the scope stays the same. Across the West Midlands, guide prices run at £59,000–£118,000 including VAT, and homes in Bartley Green, Brierley Hill and Dudley are covered too.
- Guide price
- £59,000–£118,000 inc VAT
- Time on site
- 14–22 weeks on site
- Postcodes
- B32, B62, B63, B64 and B65
- Planning rules
- England
- Local area
- Dudley
- Survey
- Free, with a written quote
What should you budget for a double-storey extension in Halesowen?
What will a double-storey extension cost in Halesowen? Our guide range is £59,000–£118,000 including VAT. That figure is adjusted for the West Midlands, about 2% below the national guide, and is intended for planning a budget. A firm written price for your chosen specification follows a free survey at your home.
| Type of job | What it usually involves | Guide in Halesowen |
|---|---|---|
| Small (15–20m² total) | A compact rear or side extension adding a small room on each floor. | £39,000–£64,000 |
| Typical (30–40m² total) | A larger kitchen or living room below with a double bedroom or en-suite above. | £59,000–£118,000 |
| Large (50m² plus total) | Wide or deep extensions, often with a new bathroom, steelwork and high-spec glazing. | £98,000–£176,000 |
Expect these to shape the final quote:
- Combined floor area across both storeys
- How the new roof joins the existing roof
- Bathrooms, en-suites and plumbing on the upper floor
- Scaffolding duration, access and the level of finishes
What’s included?
- Groundworks, foundations and below-ground drainage
- Insulated cavity walls with brick or render to match the house
- First-floor joists, stud walls and new openings upstairs
- Electrics, plumbing and heating by qualified trades, with certificates
- Windows, external doors, plastering and internal doors
- 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.
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.
For a double-storey extension in Halesowen, this means checking things like wall construction, roof structure and existing services before we put a figure on paper.
Permissions for a double-storey extension in Halesowen
As Halesowen is in England, read the following with that system of planning and building control in mind. We check what applies to your house with the council before you receive a quote.
In England, a two-storey rear extension can only be permitted development if it is no more than 3 m deep, at least 7 m from the rear boundary and finished to match the house. Most double-storey and all two-storey side extensions need full planning permission.
Building Regulations approval is needed, with structural calculations for beams, foundations and the roof. The Party Wall etc. Act 1996 often applies on semi-detached and terraced houses.
Rules change and every property is different, so we check the planning history and constraints for your address before we quote.
From survey to handover
Survey and measure
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 double-storey extension.
Quote in writing
Next you receive a written quote with a fixed price for the agreed specification. It lists what is included, what is not, and how payments are staged, so you can compare it properly.
Booking the work
Preparation matters as much as the build. We agree access, parking and working hours with you, order materials in good time, and confirm any permissions so the job isn't held up once it starts.
Finish and handover
The job proceeds in the order set out in the programme, with dust and debris kept under control. Finally we tidy away, inspect the work together and pass the finished project over to you with its paperwork.
How we work
Questions about a double-storey extension in Halesowen
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 double-storey extension, explain the options and answer questions. There is no charge and no obligation; afterwards we send a written quote.
Do I need planning permission for a two-storey extension?
Most two-storey extensions need planning permission, but it depends on the size, height and position, your home's location, whether it is listed or in a conservation area, and which UK nation you are in. In England, a two-storey rear extension can sometimes be built under permitted development if it is no deeper than 3m and at least 7m from the rear boundary. We check what applies before quoting.
How much does a double-storey extension cost?
A typical double-storey extension of 30–40m² across both floors costs £59,000–£118,000, built to a plastered finish. As a rough guide, allow around £1,400–£2,600 per square metre plus fixed costs for groundworks, scaffolding and fees. The second storey usually costs less per square metre than the first, because foundations and roof are shared. Bathrooms upstairs and a complex roof add most. We confirm a fixed price after the survey.
How is the new roof joined to the existing house?
The new roof is usually tied into the existing roof so the two read as one. On a rear extension this often means a lower ridge or a hipped end, with valleys where the slopes meet. We strip back some existing tiles, fix new rafters and battens, and lay matching tiles or slates. Lead or proprietary flashings seal the junctions so water runs off properly.
Do I need planning permission in Halesowen?
It depends on the work, the size of the project, your property type and whether the building is listed or in a conservation area. Halesowen 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 Halesowen
Whether you're in the centre of Halesowen or on its outskirts, B32, B62, B63 and B64 addresses are covered. We extend the same service, and the same fixed-price approach, to Bartley Green, Brierley Hill and Dudley.

