Page 268 - The City and Guilds Textbook: Plumbing Book 1 for the Level 3 Apprenticeship (9189), Level 2 Technical Certificate (8202) and Level 2 Diploma (6035)

The City & Guilds Textbook: Plumbing Book 1

In reality, the information has changed very little from the previous British
Standard, BS 6700: 2006+A1: 2009 Design, installation, testing and
maintenance of services supplying water for domestic use within buildings
and their curtilages, and this document should be referenced where alternative
information is not available.
The Building Regulations

The Building Regulations make reference to cold water services and systems.
These are mentioned briefly in Approved Document G1 – Cold Water Supply
and Approved Document G2 – Water Efficiency. Additional recommendations
can be found in Annex 1 – Wholesome Water and Annex 2 – Competent Person
Self-certification Schemes.
Manufacturers’ instructions

Where appliances and equipment are installed on a system, the manufacturer’s
instructions are a key document when undertaking testing and commissioning
procedures, and it is important that these are used correctly at both installation
and commissioning operations. Only the manufacturers will know the correct
procedures that should be used to safely put the equipment into operation so
that it performs to its maximum specification. Remember:
● always read the instructions before operations begin
● always follow the procedures in the correct order
● always hand the instructions over to the customer upon completion
● failure to follow the instructions may invalidate the manufacturer’s warranty.

5 THE WATER SERVICE PIPEWORK

TO DWELLINGS

Distribution of water in cities, towns and

villages

Water is supplied to our homes via a grid system network of pipes known as
trunk mains, a phrase dating back to when the mains were constructed from
hollowed-out tree trunks.

Trunk mains will vary in diameter depending on the purpose of the main and the
likely demand for the supply. Pipes that transfer water to the various points in
the distribution system can vary in diameter from 75 mm to 2.3 m. The size of
the water main depends upon the size of the community that it serves.
 Table 5.2 The size of water main required depends on the size of the community it is to serve

Town population Size of main (metres diameter)
500,000 1.05 m to 1.20 m
200,000 0.75 m
5000–20,000 0.2 m to 0.3 m

When a new house has to be connected to the water supply, the supply pipes are
usually 25 mm in diameter. At the boundary to the dwelling, a ‘screw-down stop
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