Merseyside
Larger home extension prior approval (England) in Merseyside
Up to 6 m (attached) or 8 m (detached) deep, after neighbour consultation. Rear extensions in Merseyside: we cover 41 towns including Liverpool, St Helens and Southport, with design, approvals and the build under one contract.

Merseyside 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 much does a prior approval rear extension cost in Merseyside?
A prior approval rear extension in Merseyside is priced at £1,790–£2,910 per square metre including VAT as a guide, before kitchen fit-out and fees. North West prices sit below our West Midlands baseline; access on terraced streets is the main variable.
| Size | Guide price inc VAT |
|---|---|
| 3 m wide × 4 m deep (12 m²) | £21,500–£35,000 |
| 4 m wide × 5 m deep (20 m²) | £35,500–£58,500 |
| 4 m wide × 6 m deep (24 m²) | £43,000–£70,000 |
We put a fixed price in writing once the design is agreed, and explain any provisional sums such as foundations.
Do you need planning permission in Merseyside?
If 3 or 4 metres is not enough, England's prior approval route allows 6 metres on a terraced or semi-detached house and 8 metres on a detached house for a single-storey rear extension. Neighbours are consulted, the council decides within 42 days, and the fee is £249, rising to £310 from 8 December 2026.
Conservation areas, National Parks, National Landscapes and the Broads restrict permitted development, and listed buildings always need listed building consent.
Where in Merseyside do we work?
- Liverpool
- St Helens
- Southport
- Birkenhead
- Wallasey
- Bootle
- Bebington
- Huyton
- Kirkby
- Prescot
- Thornton-Cleveleys
- Heswall
- Maghull
- Newton-le-Willows
- Formby
- Litherland
- Garston
- Speke
- Halewood
- Norris Green
- Kirkdale
- Moreton
- Haydock
- Kensington
- Fazakerley
- Hunts Cross
- Belle Vale
- Old Swan
- Allerton
- Bromborough
- Croxteth
- Prenton
- Knotty Ash
- Wavertree
- West Derby
- Childwall
- Whiston
- Dingle
- Woolton
- Mossley Hill
- Rainhill
FAQ
Questions people ask
How deep can I go with prior approval?
6 metres on attached houses and 8 metres on detached houses, single-storey only, up to 4 metres high.
Can my neighbours stop it?
They can object; the council then judges the effect on their amenity. Many schemes are approved after objections.
What happens after 42 days?
If the council has not decided, you can proceed. We still recommend waiting for written confirmation where possible.
Do you cover all of Merseyside?
We cover 41 towns and districts in Merseyside, including Liverpool, St Helens and Southport.
Who builds the extension?
Vetted building teams working under contract to us; your contract is with S&K Property Investments and Improvement Ltd.