Side extension in Basingstoke and Deane: Planning Permission Guide

A complete guide to building a side extension in Basingstoke and Deane, covering permitted development rules, costs, and professional requirements.

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Side extensions in Basingstoke and Deane at a glance

94%

approved

£548

application fee

8

weeks typical

Based on 70 decided applications in Basingstoke and Deane over 12 months (66 granted, 4 refused).

Basingstoke and Deane includes or borders the North Wessex Downs AONB — properties in or near those areas are on Article 1(5) land where permitted-development rights are restricted. Basingstoke and Deane has 43 conservation areas — extensive heritage coverage restricting external alterations across many streets. 1,620 listed buildings recorded.

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

Recent side extension decisions in Basingstoke and Deane

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

Granted

Proposed two storey and single storey front extension with a single storey side extension

RG262026-05-19
Granted

Two storey side extension following demolition of existing garage and utility

RG232026-05-14
Granted

Proposed double-storey side extension following the demolition of existing garage, conservatory and Porch

RG212026-05-12
Granted

Proposed Single-Storey Side Extension

RG252026-05-06
Granted

Erection of single storey side extension to connect house to existing Garage/Study structure. Conversion of existing garage parking to ha…

SO212026-05-04

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

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Permitted Development Rules

Class APart 1

Enlargement, improvement or other alteration of a dwellinghouse

GPDO 2015, Schedule 2, Part 1, Class A

Side extensions are also covered by Part 1, Class A of the GPDO. They must be single storey and cannot exceed half the width of the original house.

Key dimension limits

Max 2.8m width (half of house)Max 4m heightSingle storey only

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.

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Typical Costs in South East England

Side extension costs in South East England depend on the width of your side return and the specification of the build.

Single storey side extensionSouth East England

Cost per m²

£1,750£3,100

construction rate

Typical total

£27,000£50,000

Based on 10–18

Typically includes

FoundationsStructureRoofElectricsPlumbingBasic finishes

Typically excludes

Kitchen fittingPlanning application feeBuilding regs feeParty wall surveyorArchitect fees

Costs vary depending on whether the side return is narrow or full-width.

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Which Professionals Do You Need?

For a side extension, you'll typically need drawings for Building Regulations approval and may need a party wall surveyor if you share a boundary.

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.

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Conservation Areas & Listed Buildings

Side extensions are not permitted development in conservation areas or Areas of Outstanding Natural Beauty. You will need to apply for full planning permission.

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.

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Frequently Asked Questions

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