Semi-detached rear extension in Ewell

How much does a semi-detached rear extension cost in Ewell?

For Ewell we work from the South East England rate: £2,130–£3,470 per square metre of new floor, including VAT, standard specification. South East prices run above our West Midlands baseline, mainly on labour rates and clay-soil foundations.

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 semi-detached rear extension in Ewell?

Whether your semi-detached rear extension in Ewell needs a planning application depends on its size, your house and any local restrictions.

Under England's householder permitted development rules you can usually add 3 metres at the back of an attached house, or 4 metres on a detached house, without a planning application, as long as the extension stays under 4 metres high and its eaves stay under 3 metres where it is within 2 metres of a boundary.

A two-storey rear extension can be permitted development in England only if it projects no more than 3 metres, stays at least 7 metres from the rear boundary, matches the existing roof pitch and has obscure-glazed upper side windows. In practice most double-storey rear extensions go through a householder planning application.

England also has the larger home extension route: a single-storey rear extension of up to 6 metres on an attached house or 8 metres on a detached house, after prior approval from the council. The council notifies your neighbours and has 42 days to decide; the fee is £249 (£310 for applications made from 8 December 2026). The route is not available on designated land such as conservation areas.

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 Ewell like to extend?

Around Ewell the housing ranges from inter-war semis to 1960s and 1970s estates with good-sized gardens. Many of the newer estates had permitted development rights removed by condition, so we check the planning history before anything is drawn.

How a semi-detached rear extension in Ewell comes together

1. Survey visit

   We visit free of charge, measure up, check access, drainage and neighbours' extensions, and note what you want the room to do.

2. Design and guide price

   Two or three layout options with a guide price for each, so you choose the design knowing what it costs.

3. Planning and regulations

   We take the design through the right planning route, then produce the construction drawings and engineer's calculations for building control.

4. 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.

Semi-detached rear extensions near Ewell

From Ewell, the nearest places we also cover are Cheam (1.5 miles) and Epsom (1.6 miles).

• Semi-detached rear extension in Cheam
• Semi-detached rear extension in Epsom
• Semi-detached rear extension in Worcester Park
• Semi-detached rear extension in Sutton
• Semi-detached rear extension in Belmont

Other work in Ewell:

• Single-storey rear extension
• Two-storey rear extension
• Kitchen-diner rear extension
• Side return extension
• Wraparound extension
• Glazed rear extension

All rear extensions in Ewell