Understanding Old House Wiring Colours in the UK

Old house wiring colours in the UK may seem mysterious and incomprehensible, but they actually have a system that is easy to understand. The purpose of having different wiring colours is to identify which wires are most likely to be used in certain circuits. This helps electricians make sure connections are properly made, and also minimizes the risk of electrical shock. In this article, we'll discuss various aspects of old house wiring colours in the UK, including how to identify them and what types of wires are typically used in each colour.

What are Old House Wiring Colours in the UK?

In the UK, it is mandatory for all wiring installations to comply with the British Standard BS 7671. This regulation sets out the requirements regarding the design and installation of electrical wiring systems in domestic dwellings and premises. The standard calls for six different colours to be used in wiring installations; black, red, blue, yellow/green, white, and brown.

The specific colours are decided by the circuit’s purpose. For example, black is used for live wires, red for switched live wires, blue for neutral wires, yellow/green for earth wires, white for protective conductors, and brown for neutral current-carrying conductors. All these colours are used to make it easier to identify which circuits are live and which are not, and the colours must remain consistent throughout the entire wiring installation.

How to Identify Old House Wiring Colours in the UK

Identifying old house wiring colours in the UK is relatively simple. As explained, each colour is associated with a specific function or purpose and should remain consistent throughout the entire wire installation. That being said, some older wiring installations may not have been completed to the standards set out in BS 7671. In such cases, it may be difficult to determine which colours are being used.

It is important to note that the colours used in wiring installations have changed over time. For example, prior to 1904, wires in the UK were yellow and red. These colours have since been replaced, as previously stated, with black, red, blue, yellow/green, white, and brown. Thus, if you come across either of the two former colour codes, you should consult a professional electrician.

Types of Wires Commonly Found in Old House Wiring Colours in the UK

The type of wire used for old house wiring colours in the UK will vary depending on the age of the wiring installation. However, there are some common types found in most wiring installations, regardless of age. These include copper, plastic insulated, aluminium and bare copper.

Copper is the most common type of wire used in wiring installations. It is strong and durable, making it ideal for carrying large amounts of power. Plastic insulated wire is typically used in newer installations and offers a greater level of insulation than other types of wires. Aluminium is commonly used in older installations and is generally less expensive than the other types. Lastly, bare copper is used in specialized applications and offers the highest level of resistance to electricity.

Conclusion

Old house wiring colours in the UK can seem complicated, but they actually have a fairly straightforward system. Each colour corresponds to a specific function or purpose and should remain consistent throughout the entire wiring installation. That being said, due to changes over time and potential discrepancies in older installations, it is recommended that you consult a professional electrician in order to accurately identify the wiring colours in your home.

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