Rear extension in Gloucester: Planning Permission Guide

Everything you need to know about building a rear extension in Gloucester, including permitted development rules, typical costs, and which professionals you'll need.

Check if your rear extension qualifies

Rear extensions in Gloucester at a glance

97%

approved

£548

application fee

8

weeks typical

Based on 119 decided applications in Gloucester over 12 months (115 granted, 4 refused).

Gloucester borders or partially overlaps the Cotswolds AONB — properties near those boundaries are on Article 1(5) land where permitted-development rights are restricted. Gloucester has 14 conservation areas affecting external alterations in those zones. 55 Article 4 directions are in force — pre-application advice strongly recommended before any external work. 954 listed buildings recorded.

Want your personalised odds?

Approval probability, 5 nearest comparables, refusal reasons — for your specific address.

Recent rear extension decisions in Gloucester

The 5 most recent decided applications. Addresses redacted to postcode area.

Granted

Erection of single storey rear extension with accessible terrace

GL42026-05-22
Granted

Rear extension (6m x 3m x 3m)

GL32026-05-19
Granted

Works associated with the use of the property as a single dwellinghouse. Works to include: first floor rear facing window to be obscure g…

GL32026-05-15
Granted

Proposed two storey side and rear extension

GL22026-05-14
Application Withdrawn

Proposed two storey side and single storey front and rear extensions, new boundary fencing and dropped kerbs

GL42026-05-14

These are borough-wide. See the 5 nearest to your address.

Get my report — £9

Permitted Development Rules

Class APart 1

Enlargement, improvement or other alteration of a dwellinghouse

GPDO 2015, Schedule 2, Part 1, Class A

Rear extensions fall under Part 1, Class A of the General Permitted Development Order (GPDO). This means you can often build one without a full planning application, provided your project stays within the dimension limits.

Key dimension limits

Single storey

Up to 4m depthMax 4m heightMax 3m eaves height

Two storey

Up to 3m depthMust not exceed existing ridge heightMin 7m to rear boundary

These are the maximum GPDO limits for a detached house with no constraints. Your actual limits depend on your property type, location, and any planning restrictions.

Enter your postcode to see the personalised limits for your rear extension.

Check my limits

Typical Costs in South West England

Construction costs for rear extensions in South West England vary depending on size, specification, and whether you're building single or double storey.

Single storey rear extensionSouth West England

Cost per m²

£1,700£3,000

construction rate

Typical total

£22,000£44,000

Based on 12–18

Double storey rear extensionSouth West England

Cost per m²

£1,550£2,750

construction rate

Typical total

£34,000£68,000

Based on 20–35

Typically includes

FoundationsStructureRoofElectricsPlumbingBasic finishes

Typically excludes

Kitchen fittingPlanning application feeBuilding regs feeParty wall surveyorArchitect fees

Double storey extensions have a lower per-m² cost as foundations and roof are shared across two floors.

Get a personalised cost estimate based on your actual rear extension dimensions.

Get my estimate

Which Professionals Do You Need?

The professionals you'll need depend on the size and complexity of your extension, your property type, and whether you share walls with neighbours.

You'll need a party wall surveyor for this project.

Architect / designerOptional

A draughtsperson or architectural technician can prepare the plans needed for a single storey extension. A full architect may not be necessary.

Typical fee: £1,500£3,500 (Plans + Building Regs)

Structural engineerRecommended

Single storey extensions typically need structural calculations for any openings in existing walls and for foundations.

Typical fee: £500£1,500

Party wall surveyorEssential

Your semi-detached house shares a boundary with neighbours. Extensions and loft work within 3 metres of a shared wall trigger the Party Wall Act.

Typical fee: £700£1,500 (per neighbour)

Planning consultantNot needed

This guidance is based on a typical semi-detached house with no special constraints. Listed buildings, conservation areas, and attached properties may require additional professional input.

Find out exactly which professionals you need for your rear extension.

Get personalised guidance

Conservation Areas & Listed Buildings

If your property is in a conservation area, the maximum depth for a single storey rear extension is reduced to 3 metres for all property types. Two storey rear extensions are not permitted in conservation areas.

Conservation areas

Properties in conservation areas often have reduced permitted development rights. Some project types (like side extensions) lose PD rights entirely. An Article 4 Direction can remove additional PD rights.

Listed buildings

Listed buildings (Grade I, II*, or II) have no permitted development rights at all. Any external alteration requires Listed Building Consent in addition to any planning permission. An architect experienced in heritage work is essential.

Check if your property is in a conservation area or has other planning constraints.

Check my property

Prior Approval (Larger Home Extension Scheme)

What is Prior Approval?

Single storey rear extensions between 4m and 8m deep (detached) or 3m and 6m deep (other houses) may be built under the "larger home extension" scheme. This requires a Prior Approval application with a neighbour consultation — not a full planning application. The fee is lower and the decision is faster.

Frequently Asked Questions

Just want a quick yes/no for your rear extension?

Run our free 2-minute check to see whether your project likely qualifies as permitted development in Gloucester. For personalised approval odds and nearby comparables, get the full report above.

Free 2-min check