Rear extension planning drawings in Hounslow

What do rear extension planning drawings cost in Hounslow?

As a guide, £1,000–£2,500 including VAT for a single-storey rear extension, or £2,000–£3,500 for a two-storey scheme. A householder planning application in England costs £548 (£575 for applications made from 8 December 2026), and a lawful development certificate for proposed work costs half the householder fee. 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 for a rear extension in Hounslow?

Planning for a rear extension in Hounslow follows the English householder rules.

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.

Councils aim to decide householder applications within 8 weeks of validation, and prior approval within 42 days.

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 Hounslow like to extend?

Much of Hounslow is 1920s and 1930s semis and short terraces with longer gardens than inner London, which suit full-width single-storey rear extensions. Parking suspensions, skip licences and controlled hours on residential streets shape the programme more than the build itself.

How a rear extension in Hounslow 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. Drawings and budget

   Floor plans and elevations for the options, each with a guide price.

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.

Rear extension planning drawings near Hounslow

We also build rear extensions in nearby Osterley (0.9 miles) and Isleworth (0.9 miles).

• Rear extension planning drawings in Osterley
• Rear extension planning drawings in Isleworth
• Rear extension planning drawings in Heston
• Rear extension planning drawings in Cranford
• Rear extension planning drawings in Richmond

Other work in Hounslow:

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

All rear extensions in Hounslow