Extensions in Birkenhead: design, planning and build

Approvals for an extension in Birkenhead

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 England a two-storey rear extension is permitted development only if it projects no more than 3 m from the original rear wall, sits at least 7 m from the rear boundary, matches the roof pitch and uses obscure, non-opening side windows upstairs. Most two-storey extensions therefore go through a householder planning application, which costs £548 from 1 April 2026 and normally takes about 8 weeks.

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.

If the work involves a shared wall, building on the boundary, or digging foundations within 3 m (sometimes 6 m) of a neighbour's building, the Party Wall etc. Act 1996 applies and notice must be served before work starts: two months for work to a party wall, one month for new walls on the boundary and for excavations.

Applications are decided by the local planning authority (your district, borough or unitary council).

Where we work near Birkenhead

Postcode districts we cover around Birkenhead include CH41, CH42, CH44, L1, L2, L3. We also work in nearby Liverpool (2 miles), Wallasey (3 miles), Bebington (3 miles), Bootle (5 miles), Litherland (5 miles). For homes towards Cheshire, Ellesmere Port is around 9 miles away.

• Liverpool
• Wallasey
• Bebington
• Bootle
• Litherland

Guide prices for Birkenhead

Every figure below is a guide for Birkenhead, adjusted for North West England build costs (×0.95) and including VAT. Design and council fees are shown separately on each page.

Which extension suits a Birkenhead 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.

The types we would usually look at first for a home in Birkenhead are single-storey rear extensions, double-storey extensions and side return extensions, depending on the garden and how the house is laid out.