Here at UQ we have been researching Passive House certification and how that can complement other green features within a building.
One of the larger principals of passive house is to have a continuous well insulated building envelope with no air leakages. This continuous seal provide tons of health benefits for residents. Noise pollution, indoor air quality, and rodent and pest control are all helped with a Passive House building. This also really improves heating, cooling, and energy performance. In these schemes we have set the windows back or given them surrounds to provide shading when needed in the summer.
Inside the building we looked into variable refrigerant flow (VRF) systems, which provide both heating and cooling by exchanging energy in the ambient air. These systems give the resident more control over their heating and cooling needs, while also minimizing penetrations in the building envelope. Another portion of the Passive House strategy that we looked into is using energy recovery ventilators (ERV) which reuse the energy in exhausted air.
The roofs on passive house buildings need to be insulated with an R-value of 50 at a minimum and in our research we have paired that with an active green roof design which will reduce heat gain. These roofs will also have pergola style solar PV arrays assuming there is good exposure. Because these buildings will utilize a VRF system, the solar array can be sized to produce more of the building’s energy needs than is possible in a more typical residential building. This will make a near net zero more achievable than a building with conventional mechanical systems.
Though not technically part of the Passive House study, we began to look at ways to improve resiliency in future flooding events. We sought to improve the streetscape with rain gardens and right-of-way bioswales to help mitigate stormwater runoff. The roofs also harvest rainwater in underground irrigation tanks for on-site irrigation.
We hope that Passive House can become more accessible and a new standard for building design.