Explaining the New Amendment 3 to the BS7671 Wiring Regulations

Amendment 3

The third amendment made to the BS 7671:2008 (IET Wiring Regulations) includes a number of changes that came into effect on the 1st January of 2015. However, contractors have been given a six-month grace period in which they can learn about these Amendment 3 changes and make the appropriate arrangements to prepare. Therefore, the new regulations will be enforceable from the 1st June 2015 (1/1/2016 for consumers). The following is a summary of the main changes to the IET Wiring Regulations and what they mean for you.

Socket Protection

The regulations concerning socket protection have changed. Now, all sockets rated 20A and below are required to be 30mA RCD protected. Furthermore, all sockets rated up to 32A are also required to be 30mA RCD protected if they could be used to provide energy to outside portable equipment.

It should be noted that there are exceptions to these rules. Sockets rated up to 20A do not have to be protected if a risk assessment is carried out and deems this unnecessary. However, this doesn't affect installations within dwellings.

Another exception to the rule includes specifically labeled socket outlets that have been provided for particular equipment.

Consumer Units

Another addition to the regulations involves consumer units and has been prompted by an increase in fires in recent years. To combat this, consumer units should be made from non-combustible materials, for example, metal, or specialist plastic. It should be noted that this doesn't apply to commercial installations, only those completed in domestic settings.

Contractors also have the option of installing consumer units within a non-combustible cabinet. This particular Amendment 3 regulation will come into effect on the 1st of January 2016, allowing adequate time for the manufacture of necessary components.

Check out the latest amendment 3 approved consumer units here

Escape Routes

The new regulations describing wiring systems within escape routes have been devised due to a problem with these systems collapsing during fires. The premature collapse of these systems during fires has proved extremely dangerous and in some cases fatal. In response to this, the new regulations dictate that wiring systems within escape routes should be adequately supported in other to prevent collapse.


Another addition to the BS7671 is building upon the regulations concerning bathrooms. Now, low voltage circuits which pass through zones 1 and 2 off a bathroom will have to be 30mA RCD protected.


The regulations for both outdoor lighting and low-voltage lighting installations have been moved from part 5 to part 7 (714 and 715).


Amendments have been made to the protocol for the installation of cables in metal stud work walls. It is now necessary for unprotected cables to have 30mA RCD protection regardless of their depth within the wall. However, there is an exception to this if the cables can be mechanically protected during construction.


The definition of 'auxiliary circuit' has been changed to:
'Circuit for transmission of signals intended for control, detection, supervision, or measurement of the functional status of the main circuit'.

This is a just a brief outline of the new Amendment 3 changes within the IET Wiring Regulations. It is recommended that those who are affected by these regulations should ensure they are fully up to date with these changes in order to successfully function within the guidelines.

**Please also see our earlier post 17th Edition Consumer Unit Advice **