The importance of thermal insulation and thermal comfort – and their inherent relationship with wellbeing and productivity, alongside the environmental impact of the building – has been a fast growing consideration, particularly in light of aggressively evolving weather patterns and significant increase in temperatures across the country and the world.

Unfortunately, poorly insulated buildings are commonplace around Australia, leading to an overreliance on HVAC systems to maintain thermal comfort. This, of course, has significant negative environmental implications that extend well beyond the building itself. “Let’s take a house, for example. Assuming that a standard HVAC unit uses about 3.5 kilowatt to serve an average house,” says Ario Narisworoputro, Engineer at Big Ass Fans. “If every house needs an HVAC at full blast every day, across – let’s say 3.8 million homes in Australia – that is a lot of electricity that needs to be generated. And a lot of coal that has to be burnt.”

Of course, the vision of withstanding hot Australian summers without air con humming in the background may be challenging – but there are ways designers can minimise the environmental impacts of a HVAC system.

“We believe that this can be done by combining energy-efficient high volume and low speed fans with a HVAC design to reduce the HVAC load,” explains Ario. “This is because air speed is increased at occupant level and the temperature feels cooler. Using an overhead fan to circulate the air within a space allows occupants to raise the thermostat, but still provides the same cooling sensation within the room, helping to reduce greenhouse gas emissions.”

With such a pivotal role of thermal comfort from a sustainability point of view, it’s paramount for designers and engineers to consider this aspect of the project early on in the process – particularly as retrofitting is likely to generate additional, unnecessary energy, cost and material waste. “When an engineer or architect designs a building that has to meet certain standards, they certainly wouldn’t want to test it only after it's been built,” Ario adds.

That’s why industry professionals have a plethora of simulation tools available to ensure everything can be assessed early on and environmental, budgetary and time implications can be mitigated. SpecLab® is one of these tools.

SpecLab® by Big Ass Fans is a computational fluid dynamics (CFD) modelling software engineered to help designers calculate thermal comfort of a space during the project’s design phase. Anchored in real airflow data from Big Ass Fans’ Research and Development lab in Lexington Kentucky, the software combines computational fluid dynamics with airflow data enabling designers to experience how a fan selection could impact the thermal comfort and energy efficiency of the space in question.

In practice, the software builds out the project plans – complete with interior walls and other building elements or even furniture – and runs extremely precise fan simulations. Based on these, the software can calculate the minimum, maximum, and average air speeds, cooling coverage – and the corresponding cooling effects, which – of course – will depend on the occupant’s activity.

“A designer or engineer will be able to look at the data, simulate it with – for example – an air conditioning unit, and see that with a selection of fans, they will be able to specify a smaller unit – and possibly lesser amount of ducts, saving both the energy and material,” adds Ario.

On top of to that, SpecLab® performance metrics adhere to ANSI/ASHRAE Standard 55 – 2017 and ASHRAE Standard 216P which means SpecLab® is an excellent tool to prioritise thermal comfort of the occupants, environmental implications – and when considering their building’s NABERS or Green Star Ratings.