Amended Part G to the Building Regulations
Revisions to Part G (Sanitation, hot water safety and water efficiency) of the Building Regulations and a new Approved Document G have been published. Part G sets out new and amended requirements and technical guidance related to the safety and use of water in buildings.The new and amended requirements and new Approved Document came into force on the 06 April 2010.
The Requirements
The former requirements were:
The new requirements and technical guidance is set out in detail in the new Approved Document G (Sanitation, hot water safety and water efficiency) (PDF 1.27MB)
This guidance is also outlined in the LABC presentation on Part G (Copyright LABC) (PDF 3.48MB)
The new requirements are:
G1 Cold water supply
G1 is a new requirement stating that a supply of wholesome water must be provided for the purposes of drinking, washing or food preparation. thus wholesome water must be provided where drinking water is drawn off, to any washbasin, bidet, fixed bath and shower in a bathroom and to any sink in any area where food is prepared.
G1 then requires that there must be a suitable installation for the provision of water of a suitable quality to any sanitary convenience fitted with a flushing device.
The important definition here is that of 'wholesome water' which is defined as water complying with requirements contained in regulations made under section 67 (standards of wholesomeness of the Water industry Act 1991 but that non-wholesome water (for example greywater or harvested rainwater), that is water that does not meet the definition of wholesome water can be used for certain applications.
G1 applies to domestic greenhouses, small detached buildings and extensions to buildings, including conservatories if they are to be served by a water supply from a dwelling.
G2 Water efficiency
Requirement G2 and the associated new regulation 17K and 20E set out new requirements on the water efficiency of dwellings.
Requirement G2 states that reasonable provision must be made by the installation of fittings and fixed appliances.
Building Regulation 17K requires that the potential consumption of wholesome water by persons occupying a dwelling must not exceed 125 litres per person per day when calculated in accordance with the methodology set out in the CLG's document 'The Water Efficiency Calculator for New Dwellings'. (PDF, 216KB)
The WRc Group has developed an online version of the Water Efficiency Calculator for New Dwellings. This methodology is in accordance with the Government's National Calculation Methodology for assessing water efficiency in new dwellings in support of The Code for Sustainable Homes and the Building Regulations Approved Document Part G, 2009. The calculator is supported by LABC. It is hoped that the online calculator will save building designers time in paper calculations or preparing their own spreadsheets, and building control bodies time in checking calculations. WRc Group intend to develop the calculator further to include a listing of product water efficiency data.
Building Regulation 20E (and Regulation 12E of Approved Inspectors Regulations) then requires that the person carrying out the work must, within 5 days after the completion of the work, give the Building Control body a notice specifying the potential consumption of wholesome water per person per day as calculated by the above methodology in relation to the completed dwelling. A Building Control body cannot certify work to be complete until this notice has been received.
This requirement applies when a dwelling is created through new-build or conversion.
G3 Hot Water supply and systems
Requirement G3 sets out enhanced and amended provisions on hot water supply and safety. G3 applies safety provisions to all types of hot water systems and new provision on the prevention of scalding.
The former G3 only related to unvented hot water storage where as the new requirement relates to all hot water systems.
The first part of G3 is a new requirement that heated wholesome water to be supplied to any wash basin, or bidet in or adjacent to a room containing a sanitary convenience, any wash basins, bidet, fixed bath or shower in a bathroom and any sink is provided in an area where food is prepared.
The Second part of G3 is an expanded requirement that provides that any hot water system, including associated storage or expansion vessel shall resist the effects of any temperature or pressure that may occur in normal use or as a consequence of a reasonably anticipated malfunction.
The third part of G3 is an expanded requirement that provides that any part of a hot water system that incorporates a hot water storage vessel shall incorporate precautions to ensure that the temperature of the stored water does not exceed 100oC and that any discharge from safety devices is safely conveyed to a point where it is both visible and will not cause a danger to persons in or about the building.
The final part of G3 is a new requirement intended to prevent scalding and requires that the hot water supply to any fixed bath in a newly formed dwelling must be designed and installed with measures to ensure that the temperature of the water that can be delivered to the bath cannot exceed 48oC. This final part of G3 applies when a dwelling is created through new-build or conversion.
G3 applies to domestic greenhouses, small detached buildings and extensions to buildings, including conservatories if they are to be served by a water supply from a dwelling.
G4 Sanitary conveniences and washing facilities
The new G4 replaces the former G1. The requirements of G4 are, for practical purposes, broadly consistent with the former G1 and the revised technical guidance of the approved documents mainly serves to clarify the precise requirements. In particular, additional guidance is provided on the separation of sanitary accommodation from places used for the preparation of food.
G5 Bathrooms
The new G5 replaces the former G2. The requirements of G5 are for, practical purposes, broadly consistent with the former G2 and the revised technical guidance of the approved documents mainly serves to clarify the precise requirements.
G6 Food Preparation areas
G6 contains a new requirement that sinks must be provided in areas where food is prepared.
Transitional Provisions
Any work which commences on site will not be subject to the new Regulations if any of the following apply:
- where before 06 April 2010 full plans had been deposited and a decision made, and that providing that the work commences before 06 April 2011;
- where the deposit of full plans is not required, and if a contract for the proposed work had been entered into before 06 April 2010, as long as work is commenced before 01 October 2010;
- where before 06 April 2010 work has already commenced in accordance with a submitted Fulls Plans application or Building Notice and notice has been given to the local authority for commencement.
