Passive solar design
There’s nothing new here – just good, sensible design which is most effective when considered building new – at little to no additional cost. It’s upsetting how often these simple principles are overlooked in many NZ houses. They are opportunities not to be missed!
Elements of passive solar design:
• Thermal mass
Works by exposing a high-density material like an exposed concrete slab or block wall to the sun, so it can absorb the sun’s energy through the day and radiate the warmth into the house at the end of the day.
• Building location and orientation on the site
Optimisation of light and sun by ensuring certain internal spaces are facing the right direction, and the house is positioned the best way possible on the property. Applies also to sheltering internal and external spaces from wind and ensuring roof angles are optimal for solar collection.
• Passive / cross /stack ventilation
The process of supplying air to and removing air from an indoor space without using mechanical systems.
• Glass placement & passive exterior shading
Optimisation of light and control of heat gain from the sun by carefully locating window sizes and locations – and providing shading to the exterior of the building where required.
• Insulation (walls, floors, roof & windows)
Insulation is critical in preventing heat loss in cold weather, and preventing heat gain in warm weather. It comes in many forms, and also works to reduce noise pollution. It’s important to stress that while the NZ Building Code has a minimum insulation standard, it’s barely sufficient (and arguably insufficient in colder climates) and hence should be treated as that – a MINIMUM.
• Solar power collection
Clean green energy, available in many forms to heat water, preheat central heating, power appliances and electric vehicles. Photovoltaic (PV) and solar-thermal systems can be integrated into the building envelope.