A Passive House has to meet stringent building standards in order to receive certification. The design must meet three performance tests: a) energy use for heating and cooling b) total energy use for all needs c) building air tightness as measured by a blower test. Passive houses keep out the cold and conserve the warmth which means they can use up to 90% less energy than a conventional house. Although smart technology is not an essential component of a Passive House, they marry very well together. They can both help dramatically reduce building energy use.
HOW DOES A PASSIVE HOUSE ACHIEVE ALL THIS?
According to Passive House International there are certain key components that contribute to creating such an efficient unit.
The building shell, which is usually a compact box shape, consists of a super airtight envelope, with highly insulated exterior walls, roof and floor slab that retain the heat in winter and keep it out in summer. The windows are usually gas filled triple glazed, with well-insulated frames.
A Passive House is positioned and designed to maximize the heat from the sun and make sure that even in winter, when the sun is at its lowest, sunshine can still stream into as much of the house as possible. Strategic shading devices are also added to restrict the hot summer sun from pouring in through windows and thus overheating the home.
THERMAL BRIDGE-FREE DESIGN & CONSTRUCTION
Points in a building that break the insulation layer, such as windows, balconies, corners and connections, allow energy to pass through more easily. This phenomenon is known as thermal bridging. Passive houses are designed with as few thermal bridges as possible.
An excellent ventilation system makes sure you always have plenty of fresh air at room temperature without any unpleasant drafts. Heat recovery ventilators draw heat from the outgoing air and mix it with incoming air from outside in winter, and do the opposite in summer. In very humid climates, an energy recovery ventilator strips moisture from the incoming air. Fine filters keep dust, pollen and other irritants out, which is an invaluable advantage for asthma sufferers.
Passive houses still need electricity for lighting, electronics, appliances and heating water. By using solar panels on the roof, and in some cases, wind turbines, many passive house owners can be almost self sufficient, powering their homes with little or no reliance on a local energy company. The addition of smart technology enables owners to have complete control, even when not at home, over lighting, heating, cooling and security systems to further monitor energy usage and be able to make adjustments accordingly. Passive houses equipped with smart technology can make a considerable contribution towards protecting our environment.