Rear extension planning drawings in Southsea

What do rear extension planning drawings cost in Southsea?

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. 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 rear extension in Southsea?

Planning for a rear extension in Southsea 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. We check your house's planning history and any conservation area before drawing, so the route is clear before you spend on plans.

What are homes in Southsea like to extend?

Southsea has a mix of Victorian terraces near the centre and larger Edwardian and inter-war houses further out. Clay soils across much of the South East mean deeper foundations near trees, which we plan for at the survey.

How a rear extension in Southsea 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. Options and costs

   We draw layout options and price each one, so the budget shapes the design rather than surprising you later.

3. Approvals

   Permitted development check, prior approval or planning application, then Building Regulations drawings and structural calculations, plus party wall notices where they apply.

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 Southsea

We also build rear extensions in nearby Portsmouth (1.1 miles) and Gosport (1.9 miles).

• Rear extension planning drawings in Portsmouth
• Rear extension planning drawings in Gosport
• Rear extension planning drawings in Cosham
• Rear extension planning drawings in South Hayling
• Rear extension planning drawings in Hayling Island

Other work in Southsea:

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

All rear extensions in Southsea