Alterations to existing buildings
In its broadest sense, alteration can be defined as: ‘Work intended to change the function or appearance of a place.’ Ref Conservation Principles, Policies and Guidance, For the sustainable management of the historic environment, Published by Historic England in 2008.
Existing buildings often undergo alterations during their life to change, modify or improve their performance or the nature of their use.
Common examples of alterations include:
- Total or partial change of use.
- Extension.
- Partial demolition.
- Linking or separating spaces.
- Making or closing openings.
- Retrofitting a new a component or feature.
- Refurbishing an existing a component or feature.
- Renovating an existing component or feature.
- Repairing an existing component or feature.
- Maintenance.
- Decoration.
Some alterations may require planning permission. Other alterations may be considered 'permitted developments' for which planning permission is not required.
Examples of permitted developments include; certain enlargements or alterations to houses, construction of some sheds and fuel storage containers, certain porches, doors and windows, and so on. The best way to determine whether a development is permitted or not is to ask the local planning authority.
For more information see: Permitted development.
Responsibility for determining panning permissions generally lies with local planning authorities (usually the planning department of the district or borough council).
For more information see: Planning permission.
The building regulations may also apply to alterations. The building regulations set out:
- What qualifies as ‘building work’ and so falls under the control of the regulations.
- What types of buildings are exempt (such as temporary buildings).
- The notification procedures that must be followed when starting, carrying out, and completing building work.
- Requirements for specific aspects of building design and construction, such as; structure, drainage, fire safety, conservation of fuel and power, access for people with disabilities and so on.
Building regulations approvals can be sought either from the building control department of the local authority or from an approved inspector.
For more information see: Do the building regulations apply to existing buildings?
On larger projects, the The Construction (Design and Management) Regulations (CDM regulations) may also apply. The CDM regulations are intended to ensure that health and safety issues are properly considered during a project’s development so that the risk of harm to those who have to build, use and maintain structures is reduced.
For more information see: CDM regulations.
NB The 2018 International Residential Code (IRC), published by the International Code Council (ICC) defines alteration as: ‘Any construction, retrofit or renovation to an existing structure other than repair or addition that requires a permit. Also, a change in a building, electrical, gas, mechanical or plumbing system that involves an extension, addition or change to the arrangement, type or purpose of the original installation that requires a permit.’
[edit] Related articles on Designing Buildings
- Building regulations.
- CDM.
- Change of use class.
- Do the building regulations apply to existing buildings?
- Flexbury Church.
- Henry Boot Construction Ltd v Alstom Combined Cycles.
- International Existing Building Code (IEBC).
- Material change of use.
- Planning digital signage in new buildings.
- Planning permission.
- Permitted development.
- Refurbishment.
- Renovation.
- Retrofit.
Featured articles and news
Procurement in construction: Knowledge hub
Brief, overview, key articles and over 1000 more covering procurement.
Sir John Betjeman’s love of Victorian church architecture.
Exchange for Change for UK deposit return scheme
The UK Deposit Management Organisation established to deliver Deposit Return Scheme unveils trading name.
A guide to integrating heat pumps
As the Future Homes Standard approaches Future Homes Hub publishes hints and tips for Architects and Architectural Technologists.
BSR as a standalone body; statements, key roles, context
Statements from key figures in key and changing roles.
ECA launches Welsh Election Manifesto
ECA calls on political parties at 100 day milestone to the Senedd elections.
Resident engagement as the key to successful retrofits
Retrofit is about people, not just buildings, from early starts to beyond handover.
Plastic, recycling and its symbol
Student competition winning, M.C.Esher inspired Möbius strip design symbolising continuity within a finite entity.
Do you take the lead in a circular construction economy?
Help us develop and expand this wiki as a resource for academia and industry alike.
Warm Homes Plan Workforce Taskforce
Risks of undermining UK’s energy transition due to lack of electrotechnical industry representation, says ECA.
Cost Optimal Domestic Electrification CODE
Modelling retrofits only on costs that directly impact the consumer: upfront cost of equipment, energy costs and maintenance costs.
The Warm Homes Plan details released
What's new and what is not, with industry reactions.
Could AI and VR cause an increase the value of heritage?
The Orange book: 2026 Amendment 4 to BS 7671:2018
ECA welcomes IET and BSI content sign off.



















