What is a double-storey extension?
A double-storey extension (also called a two-storey extension) adds rooms on both the ground and first floor in one build. It typically gives a larger kitchen or living space downstairs and an extra bedroom or bathroom above.
How much does a double-storey extension cost in Stretford?
In Stretford, a double-storey extension typically costs £1,550–£2,350 per m² of floor area (both floors), including VAT at 20% (standard rate). For a typical 36 m² project that is roughly £56,000–£84,500. Building costs in the North West run about 6% below the UK average, and the figures for Stretford are adjusted to reflect that. Design, structural calculations and council fees are extra.
| Size or type | Guide range |
|---|---|
| Smaller project (25 m²) | £39,000–£59,000 |
| Typical project (36 m²) | £56,000–£84,500 |
| Larger project (50 m²) | £77,500–£117,500 |
| Rate per m² | £1,550–£2,350 |
The main things that change the cost:
- Scaffolding and access to the rear
- Roof design and how it joins the existing roof
- Steel beams where walls are opened up
- Brick matching and external finishes
Your exact price depends on the survey and drawings. The guide price tool gives a quick range in the meantime.
Do you need planning permission for a double-storey extension in Stretford?
Approvals for a double-storey extension in Stretford follow the rules for England. In England an extension of more than one storey can only be permitted development at the rear, no more than 3 metres deep and at least 7 metres from the rear boundary, with matching materials and any upper side windows obscure-glazed. Most double-storey extensions therefore go through a householder planning application.
Where work involves a shared wall, building on the boundary, or digging foundations within 3 metres of a neighbour’s building and deeper than its foundations (or within 6 metres for deeper work), the Party Wall etc. Act 1996 applies and notices must be served before work starts.
We check this for your address before design work starts, so there are no surprises later.
What we handle
The work we manage on a double-storey extension:
- Electrics, heating, plumbing and plastering
- Structural engineer’s calculations
- Brick or block walls, floors and a roof tied into the house
- Building control sign-off
- Opening up at both levels with steel beams
- Design drawings and planning application
How long does it take?
Allow 14 to 20 weeks on site, after planning and building control approval. Allow time beforehand for drawings and approvals, usually 3 to 4 months.
Building in Stretford
The North West has many brick terraces and inter-war semis, where kitchen extensions and dormer loft conversions add space without moving.
Projects in Stretford (M32) are surveyed in person before we quote, so the price reflects your actual property.
How it works
- 01
Visit and measured survey
A free visit to understand the project, check access and take measurements.
- 02
Design and pricing
Design options, then a fixed quote based on the chosen drawings and specification.
- 03
Permissions sorted
Applications, building control and neighbour arrangements, all before the start date.
- 04
Construction and completion
We build, put right any snags and hand over the building control certificate.
Questions about double-storey extensions in Stretford
Who approves a double-storey extension in Stretford?
Planning matters in Stretford go to the council covering your address, and the work needs building control approval. We prepare and submit the applications for you.
What drawings do I need?
Planning drawings for the application, then more detailed building regulations drawings and structural calculations for building control. We prepare both.
Will the first floor need a new staircase?
Not normally. The new rooms are reached from the existing landing, though a doorway or short corridor may need to be formed.
How much does a double-storey extension cost in Stretford?
In Stretford, a double-storey extension typically costs £1,550–£2,350 per m² of floor area (both floors), including VAT at 20% (standard rate). A typical 36 m² project comes to roughly £56,000–£84,500. Your fixed price depends on the survey and drawings.
Is a double-storey extension cheaper per square metre?
Usually yes. You pay for one set of foundations and one roof but get two floors of space, so the cost per square metre is often lower than a single-storey extension.