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 Heswall?
In Heswall, 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. That range is adjusted for the North West, where domestic building work typically costs around 6% below the national average. 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 |
Your quote will depend mainly on:
- Total floor area across both floors
- Scaffolding and access to the rear
- Bathrooms or en-suites on the first floor
- Steel beams where walls are opened up
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 Heswall?
Approvals for a double-storey extension in Heswall 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.
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.
We check this for your address before design work starts, so there are no surprises later.
What we handle
On a typical double-storey extension we handle:
- Structural engineer’s calculations
- Electrics, heating, plumbing and plastering
- Building control sign-off
- Brick or block walls, floors and a roof tied into the house
- Foundations, drainage and scaffolding
- Design drawings and planning application
How long does it take?
Build time is typically 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 Heswall
Terraced streets across the North West often suit rear dormers and single-storey kitchen extensions.
We work across Heswall and neighbouring areas such as Bebington, Birkenhead and Wallasey. Postcodes we cover in Heswall include CH60.
How it works
- 01
Visit and measured survey
A free visit to understand the project, check access and take measurements.
- 02
Drawings and written quote
We prepare the design and give you a written, itemised quote with inclusions and exclusions.
- 03
Approvals in place
We handle planning, building control and neighbour notices before work starts.
- 04
Build and handover
Work follows the agreed programme, with inspections along the way and a completion certificate at the end.
Questions about double-storey extensions in Heswall
Do you build double-storey extensions in Heswall?
Yes. We build double-storey extensions across Heswall, including postcodes CH60. Every project starts with a free home visit.
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 Heswall?
In Heswall, 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.
How close can it be to my neighbour?
Councils look at loss of light and outlook for neighbours. Many apply a 45-degree guideline from the nearest neighbouring window. We design to the council’s published guidance to give the application the best chance.
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.