In October 2013, the National Assembly for Wales passed new Building Regulations that require an automatic fire suppression system (commonly referred to as a fire sprinkler system) to be installed in new and converted homes in Wales. This come into force in January 2016.
The main standard for sprinkler systems for residential premises in Wales and England is the British Standard 9251:2005 (try and find link). This requires sufficient pressure to be delivered by the mains or to be tank fed.
All systems should have an alarm device, consisting of an electrically operated flow switch that should be initiated by the flow of water to a single head with the lowest flow.
A sprinkler system may be interfaced with the fire detection and fire alarm system (e.g. by means of a flow switch), so that a fire alarm signal is given by the building’s fire alarm system when a sprinkler head operates.
If you would like to know about the full legislation please visit http://gov.wales/newsroom/environmentandcountryside/2015/151123-sprinkler-systems-to-be-fitted-in-all-new-and-converted-housing-from-2016/?lang=en or click view this document (add doc in from email).