Rear extension planning drawings in Portishead

What do rear extension planning drawings cost in Portishead?

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. Your written price follows a measured survey and an agreed design, so it reflects your house, not an average.

Do you need planning permission for a rear extension in Portishead?

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

England's rules allow a rear extension of more than one storey without an application only when it is no deeper than 3 metres and at least 7 metres from the boundary opposite the rear wall, and never on designated land. Most two-storey schemes need householder planning permission.

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 Portishead like to extend?

Portishead has Victorian terraces nearer the centre and post-war semis on the edges. Sloping gardens are frequent, which affects floor levels and steps down to the patio.

How a rear extension in Portishead 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 Portishead

We also build rear extensions in nearby Nailsea (3.5 miles) and Clevedon (4.7 miles).

• Rear extension planning drawings in Nailsea
• Rear extension planning drawings in Clevedon
• Rear extension planning drawings in Yatton
• Rear extension planning drawings in Caldicot
• Rear extension planning drawings in Bristol

Other work in Portishead:

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

All rear extensions in Portishead