B1 Washing people
B1.7 Turning water off for plumbing maintenance 
Water isolation valves disconnect each house from the mains water supply to allow for plumbing maintenance. Known as stop valves or shut off valves, they are used when changing tap washers, repairing pipes or taps and when there is a major water leak. Valves need to be specified in housing works and consideration needs to be given to the type and location of the water isolation valve.
Survey data show that even teams with the advantage of local knowledge could not find isolation valves in over half the houses surveyed (52 per cent) and, of those valves that were found, 22 per cent were not working. Time spent by plumbers searching for isolation valves uses scarce housing maintenance funds.
If plumbers cannot find the isolation valve, they will be forced to manage repairs by either shutting off the main water supply to many houses or attempting to do repairs by reducing the water pressure, which involves opening up all taps in the house requiring maintenance. Both these options are unacceptable.
Data also shows that functioning water meters were only found in 50 per cent of surveyed houses. Water management requires basic tools such as isolation valves and water meters to be functioning to allow the housing manager to monitor water use and to assist in completing repairs to the water system of a house.
Design and specification
Ensure:
- there is an easily accessed, above ground isolation valve, for example fixed to a wall of the house, which cannot get ‘lost’ under landscaping or fencing
- the pipes to and from the water isolation valve are protected from motor cars and mowers
- the type of valve is suited to the water quality.
Consider:
- using ball valves, rather than ‘jumper’ or ‘gate’ valves, where water quality is poor
- installing a second valve on houses where the service provider insists on a below ground valve at the property boundary
- selecting water isolation valves that have fixed handles and avoid the using anti-vandal valves that do not have a handle
- installing a water meter to assist in water demand management and detecting leaks.
Quality control
During construction and before making the final payment, check that the valve:
- is of the type specified
- is located where specified and is secure
- can be turned on and off and, if it is a jumper valve or gate valve, turn fully on then back one turn to prevent the valve ‘binding’ shut in the fully open position
- if a meter was specified, it has been installed and is working.
Maintenance
As part of cyclical maintenance:
- check the water isolation valve can be turned off and on and turn jumper or gate valves fully off, then fully on, and then back one turn
- read the water meter and record water use and if a house has a high meter reading, ask the plumber to check for leaks.
| Turning water off for plumbing maintenance | Percentage of houses | Total houses surveyed | Change since 2003* |
|---|---|---|---|
| Water isolation valve not found | 52% | 3,651 | |
| Water isolation valve found and functional | 37% | 3,651 | << |
| Water isolation valve found but non-functional | 22% | 1,699 | |
| Water meter not found | 51% | 1,699 | |
| Water meter found and functional | 50% | 3,659 | + |
| Water meter found but non-functional | 26% | 3,659 |
* See ‘Changes in the conditions of houses’ for an explanation of the symbols used in this column.
Standards and references
AS 4796-2001 : Water supply - Metal bodied and plastic bodied ball valves for property service connection