Modular Rainwater HOG tanks already rate highly for their architecturally designed appearance and fit, but their additional function of providing thermal mass enables lightweight building structures to double their green points by combining rainwater harvesting with the eco benefits of high thermal mass.  

Materials with a high thermal mass operate much like thermal sponges, absorbing heat, from either the sun or internal heating sources, and slowly releasing it over a period of time.  Traditionally masonry and concrete are used for thermal mass, but water has double the R value of concrete, and Rainwater HOG tanks provide this super R value benefit in a user-friendly, easy to install format. 

Rainwater HOGs can be built into floor and wall cavities for hidden thermal benefit, or used on their side for banquette seating and thermal mass.  Rainwater HOGs can even be banked together and used as a backup bush fire-fighting water source, protected by the house structure itself from high fire temperatures which compromise other back up water systems.  

Water has been harnessed in the past for its thermal mass benefits: past systems have included “bottle walls” made of full glass bottles, and custom-cast concrete tanks built inside homes.  The Rainwater HOG module is the first water tank/thermal mass unit specifically designed to be integrated as a modular system into a built structure.  Architecturally designed and locally produced, Rainwater HOG is a true example of Aussie innovation.