The 17th Edition Wiring Regulations were updated on 1st January 2015

The new regulations will come into effect on 1st July 2015

Installations designed from 1st July 2015 should comply with the new edition

The new requirements do not apply to consumer units until 1st January 2016

Changes for IET Wiring Regulations 17th Edition Amendment 3


Key differences: –

  • Regulation Numbering System.
  • Change of title for competent persons – new title of Skilled Person (Electrically).
  • Changes to Zs values – A correction factor (known as Cmin) of 0.95 has been applied to the values of earth loop impedance (Zs).
  • RCD protection for sockets: – All sockets up with rating of up to 20A must be 30mA RCD protected.  All sockets up to 32A that could be used to supply portable equipment outside must be 30mA RCD protected.
  • Non-combustible consumer units – Consumer units now have to be made from a non-combustible or not readily combustible material when fitted in domestic premises.  This new regulation does not apply to commercial premises.  Alternatively the consumer unit may be enclosed in a cabinet or enclosure made of non-combustible or not readily combustible material.
  • Wiring systems in escape routes – Wiring systems in escape routes shall be supported such that they will not be liable to premature collapse in the event of a fire.  This means that wiring systems will have to be supported by metal fixings and cable ties or held in metal containment.  Alternatively, conductors may be retained inside non-metallic containment with metal clips or cleats.
  • Cables in metal studwork walls – now unprotected cables run in metal studwork walls will require 30mA RCD protection.
  • Auxillary circuits – there is a new definition for an auxiliary.
  • Outdoor lighting and extra low voltage lighting.
  • Bathrooms – all low voltage circuits in a bathroom to be 30mA RCD protected.
  • New Electrical Installation Certificates – The Electrical Installation Certificate has been revised.
  • Minor Electrical Installation Works Certificate.
  • Electrical Installation Condition Report.

For further information regarding these changes please contact Approved Design or your local ‘Skilled Person’ (Electrically).