Electrical wiring
[edit] Introduction
Electrical wiring is defined in the IET Wiring Regulations (BS 7671) as ‘wiring systems’, with the following definition:
| ‘An assembly made up of cable or busbars and parts, which secure, and if necessary, enclose the cable or busbars.’ |
Wiring as a term in such instances is usually taken to mean ‘cabling’ and the installation of cables within a building.
[edit] Cables and cabling
A cable, in the context of electrical installations in buildings, is an insulated conductor of electricity, usually copper or aluminium, with a protective casing which acts as an insulator. Cables are used to transmit electrical energy or data or telecommunications signals from one point to another.
The usual attributes of an electrical cable include:
- They are flexible enough to be drawn through or laid into a containment system.
- Where appropriate, they can be clipped directly or suspended from a building’s structure.
Flexible cables (often simply called flex cables), comprise finer strands of conductor material, and are used where regular movement or articulation is expected that could damage regular cables.
Cable insulation materials may comprise common plastics such as polyvinyl chloride (PVC), modified synthetic materials, or rubber. Other forms of insulation include mineral powder housed within a metallic outer casing.
The way different cables behave when subjected to fire conditions is the subject of extensive research. Toxic gas emissions, density of smoke and fire propagation speeds can vary widely with different forms of cable. This is a key consideration when selecting materials for buildings.
Since 2017, cables marketed and made available in the European Union (EU) must carry a ‘Euroclass’ classification, categorising their reaction to fire conditions.
--ECA
[edit] Related articles on Designing Buildings
- Arcing.
- Articles about electricity.
- Earthing.
- ECA articles.
- Electric.
- Electrical appliance.
- Electrical conduit.
- Electrical consumption.
- Electrical energy.
- Electrical equipment.
- Electrical installation.
- Electrical power.
- Electrical safety.
- Electrician.
- Electricity bill.
- Electrotechnical Assessment Specification guidance for installers.
- Grommet.
- IET announces release of 18th Edition Amendment 2.
- Panelboard.
- Premises wiring system.
- Ring circuit.
- Safe isolation for low voltage.
- What to know about foundation earthing.
Featured articles and news
Commissioning Responsibilities Framework BG 88/2025
BSRIA guidance on establishing clear roles and responsibilities for commissioning tasks.
An architectural movement to love or hate.
Don’t take British stone for granted
It won’t survive on supplying the heritage sector alone.
The remarkable story of a Highland architect.
The Constructing Excellence Value Toolkit
Driving value-based decision making in construction.
Meet CIOB event in Northern Ireland
Inspiring the next generation of construction talent.
Reasons for using MVHR systems
6 reasons for a whole-house approach to ventilation.
Supplementary Planning Documents, a reminder
As used by the City of London to introduce a Retrofit first policy.
The what, how, why and when of deposit return schemes
Circular economy steps for plastic bottles and cans in England and Northern Ireland draws.
Join forces and share Building Safety knowledge in 2025
Why and how to contribute to the Building Safety Wiki.
Reporting on Payment Practices and Performance Regs
Approved amendment coming into effect 1 March 2025.
A new CIOB TIS on discharging CDM 2015 duties
Practical steps that can be undertaken in the Management of Contractors to discharge the relevant CDM 2015 duties.
Planning for homes by transport hubs
Next steps for infrastructure following the updated NPPF.
Access, history and Ty unnos.
The world’s first publicly funded civic park.
Exploring permitted development rights for change of use
Discussing lesser known classes M, N, P, PA and L.
CIOB Art of Building photo contest 2024 winners
Fresco School by Roman Robroek and Once Upon a Pass by Liam Man.