Business North October 2021

86 | Respond Architects Focus on designing healthy homes Sue Russell A number of factors are considered in the design of a Passive House Certified building, including its site orientation and shading and the overall form of the building. ARCHITECTURE A Registered Architect and Certified Passive House Designer at Respond Architects, Joe Lyth has been with the practice for over five years. The business employs 24 professionals in its offices in Auckland, Wellington, Queenstown and Christchurch. In his role as BIM (Building Information Modelling) manager, Joe also oversees and liaises with the team across New Zealand, working with design software that creates 3D drawings, and is responsible for creating the design templates and training staff. After nearly 10 years working in London, he says the vibe at Respond Architects is relaxed in comparison! As a certificated Passive House Designer Joe is passionate about healthy homes, and the myriad of benefits for those who choose to build to the Passive House design standard. “New Zealand has some of the unhealthiest homes on the planet,” Joe says. “Back in the 1990’s the country was pretty forward thinking with an energy performance rating systems from South Power, however this was abandoned, and we have known for decades that our homes, while built to the building code, are unhealthy and low perform- ing,” he says. He says that traditionally the building code has resulted in designers and builders constructing to the minimum legal standard, rather than to apply best design and materials practice to ensure homes are warm, dry and well-ventilated. Joe says this is where the current code is let- ting consumers down, the minimum must be raised. As an example of what can be achieved in creating a quality living environment at min- imal ongoing cost, Joe has just built his own home to Passive House standards. The home cost less than a standard Building Code home to build, and their last energy bill was only $126 for July – the coldest month of the year “Our children were getting sick in our damp, mouldy rental home, now they are living in an environment that supports their well-being, now they’re fighting off day-care bugs in days, rather than weeks!” For a home to meet Passive House certifi - cation standards it needs to demonstrate in its building and design that it can achieve a prescribed per amount of energy input per square metre which in turn provides a warm and healthy interior environment. Joe say a number of factors are considered in the design of a Passive House Certified building, including its orientation and shading, “The Passive House standard is concerned with performance rather than how the house is built, and each home is designed for its specific site.” the form of the building (generally the simpler its shape the better its thermal capability), its site specific insulation and minimal thermal bridging, the use of high-performance win- dows and doors which meet strict airtightness standards, ventilation systems that meet energy goals and finally, efficient hot water and heating systems. “The home itself could be made of concrete, wood, straw bale. The Passive House stand- ard is concerned with performance rather than how the house is built, and each home is designed for its specific site.” Passive House Certified homes are kept warm and dry through the use of balanced heat recovery ventilation systems. “Unlike many available systems, fresh air is drawn in directly from the outside, rather than from the roof void. The fresh air is filtered, then pumped into bedroom and living areas. It flows through the building before being extracted from kitchens and bathrooms, where the air is warmest and wettest, it is then passed over a heat exchanger to transfer heat into the incoming fresh air, before being pumped back outside. “In this way the home is adequately ven- tilated with fresh air all the time, removing moisture and stale air while preventing the loss of the majority of the heat. As a member of the Passive House Institute of New Zealand, Joe says the organisation is keenly concerned with education about build- ing physics and performance. Today, the organisation has upward of 150 members who meet several times a year, and Joe is looking forward to attending the South Pacific Passive House conference in Auckland, in November. Respond Architects has a diverse team of architects, designers and technicians led by directors Natasha Cockerell and Mark Gribble. It supplies the commercial, education and residential markets with a range of design and construction services. “We have a really engaging culture with a lot of collaboration from all the team, and we get involved in exciting and innovative design projects with clients who value our capabili- ties,” says Joe. For a home to meet Passive House certification standards it needs to demonstrate in its building and design that it can achieve a prescribed amount of energy input per square metre, which in turn provides a warm and healthy interior environment.