Double-storey extensions in Wellington
A double-storey extension in Wellington starts with the right design and the right approval route. We take care of both, then build it with our own project management.
- Guide price in WellingtonFrom £36,500 inc VAT
- PlanningUsually a householder application
- Build time16–24 weeks on site
- Postcode districtsTF1, TF5

What is included
- Householder planning application where needed
- Insulation, plastering, electrics and plumbing to finish
- Breaking through at both levels, stairs and landing changes where needed
- Measured survey, design and planning drawings
- Building regulations drawings and structural design
- Ground and first floor structure, roof tied into the existing roof
The roof is what makes a two-storey extension look right or wrong. We match the pitch and materials of the main house wherever possible and plan the upstairs layout around the existing landing so the new rooms feel original rather than bolted on.
Planning rules that apply in Wellington
In England a two-storey rear extension is permitted development only if it projects no more than 3 m from the original rear wall, sits at least 7 m from the rear boundary, matches the roof pitch and uses obscure, non-opening side windows upstairs. Most two-storey extensions therefore go through a householder planning application, which costs £548 from 1 April 2026 and normally takes about 8 weeks.
Homes in conservation areas, national parks, National Landscapes (formerly AONBs), the Broads and World Heritage Sites have tighter rules, so we always check the property's status and planning history before design starts.
Building over or within 3 m of a public sewer needs the water company's consent, usually through a build-over agreement, before the foundations go in.
If the work involves a shared wall, building on the boundary, or digging foundations within 3 m (sometimes 6 m) of a neighbour's building, the Party Wall etc. Act 1996 applies and notice must be served before work starts: two months for work to a party wall, one month for new walls on the boundary and for excavations.
Applications are decided by the local planning authority (your district, borough or unitary council).
What should I budget for a double-storey extension in Wellington?
Labour and material costs vary across the UK, so for Wellington we use our West Midlands factor (×0.97). The ranges include VAT and exclude design, structural and council fees.
Typical rates in Wellington: £1,500 to £2,910 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| 3 m × 4 m, two floors 24 m² | £36,500 – £44,000 | £41,500 – £55,000 | £53,500 – £70,000 |
| 4 m × 4 m, two floors 32 m² | £48,000 – £57,500 | £55,500 – £73,000 | £71,000 – £93,500 |
| 4 m × 6 m, two floors 48 m² | £72,000 – £86,500 | £83,500 – £109,500 | £107,000 – £140,000 |
For a figure based on your own dimensions, use our guide-price tool.
Extensions in and around Wellington
Site visits are available across Wellington (TF1, TF5). Nearby, we also take on projects in Telford (3 miles), Shrewsbury (10 miles), Bridgnorth (13 miles), Market Drayton (14 miles).
Across the West Midlands, brick-built semis with long gardens are common, so single-storey and two-storey rear extensions are popular choices.
From first visit to completion
Site visits are free and there is no obligation. Where drawings are needed, the design stage is priced in writing before it starts.
Free site visit
A designer visits, takes measurements and photos, and discusses layouts, budget and timing with you.
Design and approvals
Drawings are prepared and agreed with you, then submitted for the right planning route and building regulations approval.
Fixed written price
With the design and specification agreed, you get a fixed written price and a start date.
Build and sign-off
The build is managed from start to finish, inspected at each stage and signed off on completion.
Double-storey extension questions answered
Can I see a price before committing to anything?
Yes. The guide prices on this page are adjusted for Wellington, and the guide-price tool gives a range for your own size. After the survey you get a written price before anything is agreed.
Do you cover all of Wellington?
Yes. We cover Wellington and the surrounding parts of Shropshire. Site visits are free and there is no obligation.
Who do I contract with for a double-storey extension in Wellington?
Your contract is with S&K Property Investments and Improvement Ltd, which designs and manages the project and the build teams who carry it out.
Does a double-storey extension need planning permission?
Often, yes. In England a two-storey rear extension can be permitted development only if it projects no more than 3 m and sits at least 7 m from the rear boundary, with matching roof pitch and obscure side windows. Side extensions over one storey always need planning permission. We confirm the route at the survey.
Do I need a Party Wall Agreement?
If you are in England or Wales and the work involves a shared wall or digging foundations close to a neighbour, the Party Wall etc. Act 1996 applies and notices must be served before work starts. We tell you which notices are needed.
Book a free site visit in Wellington
We will measure up, check the planning position and give you honest guide figures.
- Free, no-obligation site visit
- Planning route checked before you spend on drawings
- Written price once the design is agreed
- Building control sign-off at the end
Prefer to talk? Call 0800 088 6341 or .
Book a free site visit
Tell us a little about the project and we will arrange a time.