Rear extension planning drawings in Forest Hill

What do rear extension planning drawings cost in Forest Hill?

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 Forest Hill?

Here is how the rules in England apply to a rear extension in Forest Hill.

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 Forest Hill like to extend?

Much of Forest Hill is Victorian and Edwardian terraced housing with narrow back additions, which suits side returns, wraparounds and 3 metre rear extensions. Many streets are in conservation areas, gardens are short, and almost everything comes through the house or along a rear alley.

How a rear extension in Forest Hill 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. Approvals

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

4. Build and sign-off

   We build to the approved drawings with regular updates, then hand over the building control completion certificate and any guarantees from suppliers.

Rear extension planning drawings near Forest Hill

From Forest Hill, the nearest places we also cover are Crofton Park (0.5 miles) and Perry Vale (0.7 miles).

• Rear extension planning drawings in Crofton Park
• Rear extension planning drawings in Perry Vale
• Rear extension planning drawings in Catford
• Rear extension planning drawings in Ladywell
• Rear extension planning drawings in Brockley

Other work in Forest Hill:

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

All rear extensions in Forest Hill