West Derby, Merseyside
Two-storey rear extension in West Derby
For homes in West Derby, a two-storey rear extension is often the simplest way to gain space without moving. A larger kitchen downstairs and an extra bedroom or bathroom upstairs, under one roof. We take it from survey to completion certificate.
We cover West Derby (L11, L12 and L13) as part of our Merseyside work. Two-storey rear extensions suit semi-detached houses in West Derby best, where the extra bedroom matters as much as the bigger kitchen.
Book a free site visit
Tell us about the house and we'll call to arrange a free, no-obligation visit.
How much does a two-storey rear extension cost in West Derby?
For West Derby we work from the North West England rate: £1,690–£2,540 per square metre of new floor, including VAT, standard specification. North West prices sit below our West Midlands baseline; access on terraced streets is the main variable.
| Size | Guide price inc VAT |
|---|---|
| 3 m × 5 m footprint, two floors (30 m²) | £51,000–£76,000 |
| 4 m × 6 m footprint, two floors (48 m²) | £81,000–£122,000 |
Ground conditions, glazing, the roof and how far the house is opened up move the final figure within the range.
Do you need planning permission for a two-storey rear extension in West Derby?
Whether your two-storey rear extension in West Derby needs a planning application depends on its size, your house and any local restrictions.
England's rules allow a rear extension of more than one storey without an application only when it is no deeper than 3 metres and at least 7 metres from the boundary opposite the rear wall, and never on designated land. Most two-storey schemes need householder planning permission.
Conservation areas, National Parks, National Landscapes and the Broads restrict permitted development, and listed buildings always need listed building consent. Before any drawing we look up the property's history with the council, because earlier extensions and removed rights change the answer.
What are homes in West Derby like to extend?
West Derby has long runs of terraced houses with back yards and alleys, plus 1930s semis further out. Yard extensions on terraces are often single-storey and close to both boundaries.
How a two-storey rear extension in West Derby comes together
Survey visit
We visit free of charge, measure up, check access, drainage and neighbours' extensions, and note what you want the room to do.
Design and guide price
Two or three layout options with a guide price for each, so you choose the design knowing what it costs.
Approvals
Permitted development check, prior approval or planning application, then Building Regulations drawings and structural calculations, plus party wall notices where they apply.
Fixed price and build
A written price for the agreed design, a start date and a named contact through the build, ending with the building control completion certificate.
Two-storey rear extensions near West Derby
From West Derby, the nearest places we also cover are Norris Green (1.0 miles) and Knotty Ash (1.3 miles).
- Two-storey rear extension in Norris Green
- Two-storey rear extension in Knotty Ash
- Two-storey rear extension in Croxteth
- Two-storey rear extension in Old Swan
- Two-storey rear extension in Fazakerley
Other work in West Derby:
FAQ
Two-storey rear extension questions in West Derby
Do I need a party wall agreement?
In England, usually yes if the extension is on or near a shared boundary or the foundations are close to a neighbour's building. We serve the notices.
Will I need a structural engineer?
Yes for the beam over the new opening and usually the foundations; we arrange them and their calculations go to building control.
Does a two-storey rear extension need planning permission?
Almost always. England and Northern Ireland allow 3 metres without an application only if at least 7 metres remains to the rear boundary; Wales and Scotland are similar or stricter.
Is the site visit in West Derby free?
Yes. We visit, measure up and talk through the options with no cost and no obligation.
Can you match the brick or stone on my West Derby house?
We source the closest match and show you samples before ordering; reclaimed materials are often the best match on older houses.
What postcode areas do you cover around West Derby?
Including L11, L12 and L13, and the surrounding Merseyside area.