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 Ely?
In Ely, a double-storey extension typically costs £1,750–£2,650 per m² of floor area (both floors), including VAT at 20% (standard rate). For a typical 36 m² project that is roughly £63,000–£95,500. The guide for Ely reflects typical costs in the East of England, roughly 6% above the UK-wide figure. Design, structural calculations and council fees are extra.
| Size or type | Guide range |
|---|---|
| Smaller project (25 m²) | £44,000–£66,000 |
| Typical project (36 m²) | £63,000–£95,500 |
| Larger project (50 m²) | £87,500–£132,500 |
| Rate per m² | £1,750–£2,650 |
What moves the price most:
- Brick matching and external finishes
- Scaffolding and access to the rear
- Total floor area across both floors
- Bathrooms or en-suites on the first floor
A guide range is only a starting point: the guide price tool gives an instant figure for your size, and a free survey turns it into a fixed quote.
Do you need planning permission for a double-storey extension in Ely?
Before anything is built in Ely, we confirm which approvals apply in 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.
Building regulations approval comes from the council’s building control service or a registered building control approver. The work is inspected at key stages, such as foundations, drainage and insulation, and a completion certificate is issued at the end.
Our first visit includes a check of your planning history, so you know the route before paying for drawings.
What we handle
What we take care of:
- Windows, doors and staircase alterations
- Foundations, drainage and scaffolding
- Brick or block walls, floors and a roof tied into the house
- Opening up at both levels with steel beams
- Design drawings and planning application
- Structural engineer’s calculations
How long does it take?
Expect 14 to 20 weeks on site, after planning and building control approval. Before that, surveys, drawings and approvals usually take 3 to 4 months, longer if the council asks for changes.
Building in Ely
Across the East of England, 1930s and post-war semis, newer estates and rural cottages all feature, each with different extension and loft options.
We work across Ely and neighbouring areas such as Newmarket, March and Cambridge. Postcodes we cover in Ely include CB7.
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
Approvals
Planning or permitted development confirmation, building regulations and any party wall matters.
- 04
Construction and completion
We build, put right any snags and hand over the building control certificate.
Questions about double-storey extensions in Ely
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.
Who approves a double-storey extension in Ely?
Planning matters in Ely go to the council covering your address, and the work needs building control approval. We prepare and submit the applications for you.
How much does a double-storey extension cost in Ely?
In Ely, a double-storey extension typically costs £1,750–£2,650 per m² of floor area (both floors), including VAT at 20% (standard rate). A typical 36 m² project comes to roughly £63,000–£95,500. 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.
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.