1.15.2 Mechanical Services

Overall Design and Performance

The design and installation, together with the future maintenance of the mechanical installations should reflect the needs and demands of the various functions that will take place in the Stations as shown in the Zone Data Sheets. The provision and operation and maintenance of effective heating and ventilating systems, hot and cold water supplies, drainage, gas and compressed air installations and lifts must meet the performance criteria set out in this Output Specification and demonstrate how it integrates with the design of the buildings.

Pipework and ductwork branches should run horizontally, generally in readily accessible ceiling voids and vertically in purpose provided accessible builder's work enclosures.

The HVAC System should be monitored and capable of remote adjustment via a Building Management System (BMS).

The use of energy minimising systems should be investigated as a matter of course.

Heating and Thermal Comfort

The internal air temperature shall generally be in accordance with the Zone Data Sheets.

Multi-purpose areas of the Stations shall have heating equipment capable of being controlled to deliver the required temperature to suit the variety of activities proposed, such controls being operated by an Energy Management System.

Surface temperatures of static heat emitters and associated pipework must be safe and satisfy any current legislation on safety matters. Temperatures must be maintained evenly within spaces and not create great variances at floor or ceiling (roof) levels.

The Contractor should provide a zoned system designed to meet the various functions that will take place within the buildings at differing times of use. These zones will be required to have variable temperature and time controls to permit extended use outside the agreed 'core' hours. Space heating controls should be straightforward to operate and be as far as possible automatic as set out in the Zone Data Sheets.

Ventilation Systems

In addition to the ventilation of all internal spaces to the required CIBSE standards, consideration must be given to 'special' ventilation requirements of special areas of the buildings (for example, fire appliance bays, workshops, kitchens, drying rooms, kitchens, custody suites, photographic units, forensic laboratories etc.)

The building design must reduce heat gains wherever possible in order to reduce the need for mechanical ventilation or cooling to offset high room temperatures. Preference should be given to passive means of reducing heat which in themselves do not exacerbate the consumption of energy.

Water Installations

Mains water shall be supplied direct to kitchens / vending machines / drinking fountains and other outlets as set out in the Zone Data Sheets. The design should provide for 40 litres per person cold water storage for a period of 8 hours usage. Harvested or grey water should be considered for installation to toilets but must on no account be applied to detainee areas of Custody Suites.

The Contractor should undertake the design of all systems to ensure that the risk of Legionellis is avoided and that plant or water systems are so designed and constructed that they will be safe and without risk to human health when used.

Hot water systems should utilise low energy solutions such as evacuated tube thermal heating plant to reduce overall energy consumption.

Gas Installations

All gas installations and appliances installed must comply fully with the current Regulations or other relevant guidance and with the manufacturer's directions. Adequate free air supply to rooms in which any gas burning equipment is installed must be provided

Automatic Controls

The Contractor should provide a complete Building Management Systems (BMS) to serve the building. This should comprise an automatic control system including Motor Control Centres, outstations, temperature control, alarm and indication systems and should be supplied, installed, tested and commissioned as part of the Services. The BMS should have the facility for remote monitoring and if necessary be compatible with the Authority's existing BMS equipment.