A new breed of sustainable housing has landed in Sydney’s inner-city with the opening of The Fern.
The 11-unit development from Steele Associates is Australia’s first certified Passive House high-rise project. It endeavours to “set a new standard in sustainable urban living where luxury, lifestyle and comfort co-exist.”
“This is a significant milestone for construction in Australia,” says Chris Nunn, AMP Capital Real Estate’s Head of Sustainability. Nunn represented the Australian Passive House Association (APHA) at The Fern’s opening event, held in late November.
“It will showcase to the market that a better-quality building product is possible, it’s attractive and it delivers outcomes we all want – higher comfort and lower energy costs.”
There are over 50,000 passive homes around the world. Many of them are in European cities, though the movement is spreading with building designers adapting guidelines to suit their given climates.
“Only about six months before we started building did I discover Passivhaus,” says The Fern’s architect, builder and developer Oliver Steele of Steele Associates. “We had a huge learning curve on the job, but we learned a lot.”
It appears to be a lesson that has paid off, with Steele committing to make his next build, a six-unit apartment block, starting in January, another Passivhaus project.
This also fits in with APHA’s stated vision of Australia’s future – a future built through “healthy, comfortable, low energy, resilient buildings” across residential complexes, schools, hospitals, office buildings and beyond.
In its design and installation, a Passivhaus structure invokes rigorous standards around its core principles. Nunn and Fantech’s Joel Seagren, M.AIRAH, who serves as APHA Director (Secretary), explain these elements:
This means that buildings will stay warmer in winter and cooler in summer.
Airtight construction with mechanical ventilation and heat recovery
Combined, these elements deliver building structure durability, indoor air quality and energy efficiency. They create a building where the money spent on heating and cooling the space doesn’t leak out via gaps in the walls, floor, roof, windows and doors; excellent indoor air quality is maintained; and the building structure is not compromised by condensation, mould growth and, ultimately, failure.
Minimising thermal bridges
In summer, the sun that hits the window frames and balconies doesn’t radiate into the space and create a problem that can only be solved with air conditioning. Likewise, in winter the warmth inside the space doesn’t escape through cold window frames, steel beams or concrete slabs.
This helps keep out the heat of the sun in summer while admitting the right amount of natural light. It helps keep the building warmer in winter by keeping heat inside. It also means that outside noise is blocked, so The Fern apartments will be peaceful despite the busy urban surroundings.
Although Passivhaus can provide increased energy efficiency, there are challenges with using the approach within Australia’s building code. One example Steele gives is the use of heat recovery ventilation (HRV).
With HRV, the system delivers a constantly operating, low-volume swap – delivering filtered, fresh air to living and sleeping areas while extracting stale air from wet areas and kitchens. This ongoing approach differs from the Australian standard of a two-minute rapid ventilation system.
“If we complied with the code, deemed to satisfy, then we would have a bulky, expensive, unnecessary mechanical ventilation system as well as a heat recovery ventilation system,” says Steele.
To prove the Passivhaus approach to ventilation is a viable alternative, Steele and some partners used The Fern as a test case. During the build, they developed a solution using a standard approved by the American Society of Heating, Refrigeration and Air-Conditioning Engineers (ASHRAE).
They were successful in their aims – HRV is now recognised as an alternative solution to the traditional mechanical standard.
Steele points to other features of The Fern’s design such as fire-stopping and air tightness as well beyond compliance. He also notes that thanks to the rigorous construction protocols, the 2kW split system air conditioner in each apartment is more than enough to provide cooling in the middle of a Sydney summer – an improvement over the 8kW system generally used in traditional developments.
Steel says the design approach pays off in terms of cleanliness too. “It’s cockroach proof, dust proof and pollen proof.”
APHA believes that The Fern represents a significant achievement in urban design and should serve as a demonstration project as to what’s possible for the Australian real estate industry.
“Passive House-certified buildings set a new standard in quality,” says Nunn. “They deliver outstanding comfort, ultra low-energy consumption and are more resilient to the predicted impacts of climate change, particularly heat waves. This supports the city of Sydney’s vision to be carbon neutral in a really meaningful way.
“We need to be building projects like The Fern if we’re going to make a real contribution in the fight against climate change.”