Whether it be a large commercial building, an industrial site, a multi-unit residential or a single residential house, good passive design can significantly improve user comfort while remaining environmentally friendly. Ania Hampton explains.

Architects and designers are under increasing pressure to meet the (sometimes) conflicting objectives of a delivering a ‘green’ building that also provides high levels of occupant comfort. While home owners and those responsible for commissioning schools, offices, warehouses and other types of buildings want to do the right thing environmentally, they do not want to sacrifice winter warmth or summer cool.

“Everyone wants a building that operates at 21-24ºC all year round,” says Ania Hampton, director of Hampton Sustainability, an ESD consultancy based in Melbourne.

“If you just look at Facebook over summer you’ll see how many people were complaining about the heat in their homes and offices. Thermal comfort is probably the number one factor in most people’s satisfaction with buildings.”

A mechanical engineer by training, Ania has shifted her focus from mechanical and electrical systems that deliver occupant comfort to a user-led focus with emphasis on passive design principles and client engagement.

She sees client engagement as an essential part of delivering a user friendly building for a number of reasons:

• The first and most obvious is to have happy occupants – and you won’t have happy building occupants if they have not been consulted during the design process and if their needs have not been taken into account. For residential projects, this is a relatively simple proposition, but for commercial projects of any size, Ania recommends a task force of actual building occupants be established early in the project.
• Most clients say that what they want is ‘a sustainable building’ or ‘a green building’, without a detailed understanding of what they actually want in operation. So an essential element in designing user friendly buildings is to educate clients and occupants to help them set appropriate expectations. It’s simply not possible to deliver a green building that maintains that temperature range of 21-24ºC year round, and in fact that may not maximise occupant comfort anyway – Ania points out that 22.5ºC can feel uncomfortably cool on a day where outside temperatures reach 40º
• A related facet of client and occupant education is the need for building users and operators to understand their roles in occupying and running the building. This critical step of education can be the difference between a building operating at its best, and one that fails to perform as expected. Seemingly simple things like instructing cleaners to leave windows open where the building is designed to purge heat overnight can have dramatic effects on occupant comfort.

Having engaged both client and occupier representatives during the “requirements gathering” phase of the project, designers can progress to a building design that employs passive design techniques. While principles such as site orientation and thermal mass have been the stock-in-trade of designers for decades, Ania points out that passive design has evolved, with designers now seeking to meet occupant comfort objectives through fabric choice and by integrating natural ventilation and other passive comfort control strategies in conjunction with, or instead of, traditional electrical and mechanical services.

Ania’s ‘Top 5’ tips for designing high performing green residential projects are:

1. Planning, planning, planning. The more you can map out the use and occupancy of a building, the more you can make it support your users’ needs. If a home office demands closed windows for noise protection, how will you ensure adequate ventilation? If sleeping zones cannot be protected from harsh winter and summer conditions, what is the most effective way to heat and cool them? Better to accept that heating and air conditioning is required, and install appropriately sized, high efficiency units, says Ania, than to eschew them altogether but then rush out and buy “the cheapest unit at Bunnings” during a hot spell.
2. Orientation – aim to have living areas on the north side to gather winter sun and site laundries, garages and other utility areas to the west, as these low-use areas will shield the rest of the home from the hot afternoon sun.
3. Ceiling fans! Useful for circulating air for cooling in summer, and driving heated air downwards from the ceiling in winter, don’t underestimate the effect of this simple appliance on user comfort.
4. Shading features – external blinds, verandas and/or plantings of deciduous trees or vines to provide summer heat protection and cooling effect without minimising available winter sunlight.
5. Insulation and good quality glazing. Not sexy, but essential.

Most of the same design principles apply to small offices, schools, community buildings and retail outlets, although the savvy designer is conscious of the different hours and types of occupancy. Retail outlets for example may want to operate with the door open during business hours (including peak hours of summer heat) to encourage customers in, which has obvious effects on any heating and cooling systems in place.

And Ania’s number one tip for high performing buildings? User education and training. Educate your clients and building occupants about the design decisions that have been made, the reasons behind them, and what occupiers need to do to utilise that design. Is the building automated or do people need to turn off lights and air conditioners? Should windows be opened at night or during the day? Blinds up or down in different times and different seasons? People really need to experience their building across all four seasons and learn the ways to drive the building for maximum comfort, Ania stresses. She encourages clients to use small weather stations to monitor weather patterns and open or close up the house or building according to prevailing weather conditions. It’s essential to keep experimenting, she suggests, as it can take a while to “get it right”. Encouraging occupiers to take responsibility for the performance of their buildings is the number one way to reap the performance benefits of passive design.