Extending your home in Merseyside
Looking to extend your home in Merseyside? Start here: extension types, guide prices for Merseyside, the planning rules that apply and how a project runs.
- Towns listed17
- Price regionNorth West England (×0.95)
- Planning rulesEngland
- Postcode districts59
Towns we cover in Merseyside
Towns we cover here include Liverpool, Birkenhead, St Helens, Southport.
Planning rules in Merseyside
In England a single-storey rear extension can usually go up to 3 m beyond the original rear wall of a semi-detached or terraced house, or 4 m on a detached house, without a planning application, provided it is no more than 4 m high, keeps eaves to 3 m within 2 m of a boundary and, with other buildings, covers no more than half the land around the original house. The larger home extension prior approval scheme raises those depths to 6 m and 8 m, with neighbours notified and a 42-day decision.
In a conservation area, national park, National Landscape, the Broads or a World Heritage Site the permitted development limits are tighter (no side or two-storey extensions without an application). Listed homes need listed building consent, and if permitted development rights have been removed, any extension needs an application.
Building regulations approval is separate from planning. In England you can use the council's building control team or a registered building control approver; a full plans application gets the drawings checked before work starts, and the inspector signs the work off with a completion certificate.
What extensions cost in Merseyside
We publish guide prices so you can budget before anyone visits. For Merseyside they are adjusted by ×0.95, the factor we use across North West England.
| Extension type | Example size | Standard spec (inc VAT) |
|---|---|---|
| Double-storey extensions | 32 m² | £54,500 – £71,500 |
| Extensions over a garage | 12 m² | £23,500 – £31,000 |
| Single-storey rear extensions | 20 m² | £38,500 – £49,500 |
| Wraparound extensions | 25 m² | £54,500 – £69,000 |
| Orangery extensions | 16 m² | £42,500 – £53,500 |
Which extension suits a Merseyside home?
The North West has a high share of Victorian and Edwardian terraces with rear yards and outriggers, plus large areas of inter-war semis in the suburbs.
Depending on the plot, single-storey rear extensions and kitchen extensions are often the strongest options, with side return extensions worth considering where there is room.
Every extension type in Merseyside
- Glass box extensions · from £28,500
- Kitchen extensions · from £25,500
- Orangery extensions · from £28,500
- Planning permission for extensions · from £300
- Side return extensions · from £17,000
- Home office extensions · from £15,000
- Pitched roof extensions · from £21,000
- Wraparound extensions · from £34,000
- Bedroom extensions · from £24,500
- Bungalow extensions · from £24,500
- Annexe extensions · from £52,000
- Extensions over a garage · from £22,500
- Extension plans and drawings · from £1,100
- Single-storey rear extensions · from £19,500
- Conservatory replacement extensions · from £19,000
- Timber frame extensions · from £19,500
- Side extensions · from £20,500
- Flat roof extensions · from £19,500
- Building regulations for extensions · from £850
- Double-storey extensions · from £36,000
- Utility and boot room extensions · from £13,000
- Porch extensions · from £3,800
Neighbouring areas
Questions about extensions in Merseyside
How much does an extension cost in Merseyside?
With our North West England factor (×0.95), a standard-spec 20 m² single-storey extension is a guide £38,500 to £49,500 including VAT. Prices for every type are linked on this page.
How long does an extension take in Merseyside?
Usually 2 to 4 months of design and approvals, then 10 to 16 weeks on site for a single-storey extension or 16 to 24 weeks for two storeys.
Can I get a price before anyone visits?
Yes. This page shows guide prices adjusted for Merseyside, and the guide-price tool gives a range for your own size and finish in about a minute.
Will my neighbours need to be told?
If you apply for planning or prior approval the council notifies them, and in England party wall notices may be needed for work near a shared boundary.
Book a free site visit in Merseyside
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.