Project
and ducting concealed within a corner ceiling bulkhead . The mezzanine floor is served by a single fan coil unit , exposed within the open roof space , and exposed spiral wound ducting with sidewall grilles .
RESIDENTIAL ( APARTMENTS ) There are a total of 104 apartments as part of the Bridgewater development . Eighteen of these ( on levels 1 and 2 ) are serviced apartments for exclusive use of the hotel . The remaining apartments are intended for private ownership and comprise of one or two bedroom units plus twelve luxury penthouse units on the top two floors .
The apartments ( with the exception of the penthouse units ) are generally not air conditioned . Two central fan powered systems provide extraction ventilation from all bathrooms , whilst two central fan powered systems supply filtered ( unconditioned ) fresh air to the apartment corridors and lift lobbies , as well as to the penthouse units and the 18 serviced hotel units .
An example of apartments ’ corridor services .
RACA Journal | Benjamin Brits
Figure 4 : The apartment corridor services in the 3D model .
The penthouse units have air conditioning in the lounge / dining room as well as in the master bedroom . This is by means of Samsung AR range digital inverter mid-wall split ( DX ) units , with the condensing units installed in close proximity to the indoor units , on the open roof slab .
The architectural intent was for all services in the apartment corridors to be fully exposed to view , which presented a challenge to the MEP consultants in terms of neat and functional co-ordination of such services .
WSP
The extract fans have variable speed drives which are linked to CO sensors in each basement , thus allowing the fans to operate at lower volumes ( and hence reduced energy consumption ) in times of low usage of the parking basements . Both fans have Class H rated motors and double up as smoke extract fans in the event of a fire . The fans start up automatically to run at full speed , on receipt of a double knock signal from the fire detection system .
Fresh air is drawn into each basement level via three large shafts located on the opposite side to the extraction systems , with air drawn in ( induced ) through large weater louvres on ground floor level .
PARKING BASEMENTS There are two levels of basement parking located below the full footprint of the development . These basements are mechanically ventilated , with each having its dedicated extraction fan , both fans being located in a common plant room on the upper basement .
The design of the layout of this plant room proved to be a considerable challenge due to the extremely tight space constraints ( see photo below ). Acoustic type exhaust air weather louvres were installed due to the location of the offices directly above this plant room .
The basement fan plant room showing the extreme space constraints .
RACA Journal | Benjamin Brits
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RACA Journal I January 2022 www . hvacronline . co . za