Mark Rooftop – Solar Hot Water

Collins Street, Melbourne CBD

  • Design Phase Commencement: July 2004
  • System Commissioning: April 2005

Client: Airspace Developments

Project Goals

Provide a central solar hot water system for 27 rooftop apartments.


The Mark Building is a prestigious Collins Street address and Mark Rooftop is three levels of apartments built on the roof space.

Initially the client requested both photovoltaic and solar hot water systems; however, significant shading from the adjoining buildings ruled out the photovoltiacs.

A centralised solar hot water system was selected, as this provides better economies – given that not all the apartments will be occupied all the time. The solar hot water panels were mounted on the new apartments’ rooftop and positioned for maximum solar gain. Hot water from the solar panels is pumped to storage tanks mounted on the side of the building. Five solar storage tanks feed two gas boosted tanks, which in turn are connected to 27 apartments by a ring main. Each apartment has its own tempering valve to deliver water at safe temperatures.




The client has used the solar hot water system as a feature in marketing the apartments.