Building Regulations - Wales: Amendments to Part G and new Part Q coming into force 1 November 2018

9 July 2018

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The Welsh Assembly Government have published amendments to Part G and a new Part Q for use in Wales. The new requirements will come into force on 1 November 2018.

The changes are summarised below.

Amendments to Part G - Water efficiency of new dwellings

Building Regulations requirements

Regulation 36 revised

  • For new dwellings a more stringent provision of 110 litres per person per day is to be implemented, changed from 125 litres per person per day.
  • Any dwellings formed by a change of use will remain at 125 litres per person per day.
  • Reference to ‘The Water Efficiency Calculator for New Dwellings: published by the DCLG’ replaced by ‘reference to ‘in accordance with a methodology approved by the Welsh Ministers’


New requirement in schedule 1 for ‘water efficiency of buildings (other than dwellings and healthcare buildings)’

Applies to all new buildings and extensions other than:

  • Dwellings
  • Healthcare buildings

Healthcare buildings mean:

  • A hospital
  • Certain buildings used for the provision of medical and dental services
  • Certain care homes

Approved Document G

  • The list of competent persons schemes for sanitation, hot water safety and water efficiency in Annex 2 of Approved Document G has been removed and a cross reference is now made in the AD to the competent person self-certification schemes under Schedule 3 of the Building Regulations.
  • Annex 2 (Competent person self-certification schemes relevant to sanitation, hot water and water efficiency) is now replaced by ‘Annex 2 Water efficiency calculator for new dwellings’.
  • The full methodology is now in Annex 2 of Approved Document G and this is referred to as the ‘water efficiency calculator’.
  • An alternative fittings approach is introduced for new dwellings (cannot be used for change of use).

Requirement G2A

New guidance introduced to support Requirement G2A which is based on a performance standard that gives maximum fittings consumption figures for:

  • WCs
  • Urinals
  • Wash hand basin taps
  • Showers

New Requirement Q - Security - unauthorised access

Statutory requirement

Same statutory requirement as England but with reference for the need to ‘deter and resist’ unauthorised access. England just refers to ‘resist’ unauthorised access.

Part Q in Wales applies solely to newly erected dwellings whereas Part Q in England also applies to dwellings formed by a change of use.

Approved Document Q


Additional reference in Approved Document Q Wales to detailing the provisions necessary to ‘deter unauthorised access’.

This applies to:

  • Entrance doors into a dwelling
  • Entrance doors and communal areas of a building containing dwellings

Measures – security lighting will meet the requirement if it can act as a deterrent against crime.

Section 1 - Doors

In Wales guidance for interconnecting doorsets refers to garages and conservatories.

In England the guidance refers solely to garages

In Wales reference is made to PAS 24: 2016

In England reference is made to PAS24:2012

In Wales reference is made to Secured by Design’s New Homes 2016

In England reference is made to Secured by Design’s New Homes 2014

In Wales there is no reference to DHF specification TS 008:2010 for letter plates

In England Letter plates meeting DHF specification TS 008:2012 are deemed to protect against attacks

In Wales the Note to paragraph 1.4 regarding alternative caller-identification measures does not exist.

Section 2: Windows

In Wales reference is made to PAS 24: 2016

In England reference is made to PAS24:2012

In Wales reference is made to Secured by Design’s New Homes 2016

In England reference is made to Secured by Design’s New Homes 2014

Section 3 – Security Lighting

Section 3 – Security Lighting applies in Wales but not in England.

In Wales all elevations containing entrance doors into a dwelling or the entrance doors and communal areas of a building containing dwellings should have external security lighting.

Transitional provisions

The amendments to Part G and the new Part Q in Wales come into force on the 1 November 2018.

These changes do not apply where:

  • an initial notice or amendment notice for the building work is served on or before 1 November 2018 provided that work on site is commenced before 1 November 2019

Commencement of work

The Welsh Government has not confirmed what they would consider as a suitable commencement on site for the purposes of these changes. However for previous regulation changes the Welsh Government’s opinion of commencement of work would usually be marked by work such as:

  • excavation for strip or trench foundations or for pad footings
  • digging out and preparation of ground for raft foundations
  • vibroflotation (stone columns) piling, boring for piles or pile driving
  • drainage work specific to the building(s) concerned.

The Welsh Government considers that the following sorts of work would not be likely to constitute the commencement of work:

  • removal of vegetation, top soil or removal/treatment of contaminated soil
  • demolition of any previous buildings on the site
  • excavation of trial holes
  • dynamic compaction
  • general site servicing works (e.g. roadways)

In some cases applications will be in respect of a number of buildings on a site, for example a number of houses. In such cases it is the commencement of work on the first of the buildings within the application which determines whether all the building work can take advantage of the transitional provisions, not each individual building.

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