A big trend across the world is to make buildings of all kinds more energy efficient, more environmentally friendly. While there are plenty of ideas about how to do this, one of the leading concepts for a complete approach to the task is called Passivhaus. But how can you make your home more Passivhaus?
Basic principles
The basic principles of Passivhaus are being applied to new build properties across Europe and there are elements that can be added to existing properties too. The aim is to reduce the heating requirements of the property by 75% in comparison to the new standard practises. It has been used in some 20,000 new properties since it was developed in Germany in 1998.
To retrofit your home in ways that make it more Passivhaus may not be the cheapest undertaking but there are gains to be made in the long run, most notably lower utility costs. Then there is the feeling of achievement, of doing your bit to improve your little corner of the world. Here are some ideas from those who have done just this.
Super Insulation
One of the big principles of Passivhaus is that the house is insulated to a U-value of less than 0.15 Wm2K. To do this, a new level of super insulation is required throughout the house. All insulation reaches a certain standard but the new super insulation is both thinner than standard products and more efficient. It can be added to walls, floors and as part of roof construction.
Structural Insulated Panels (SIPs)
SIPs are able to achieve the required 0.15 mark without the need for additional insulation. They use a special jointing arrangement that can run through the walls and roof of the building and means that thermal bridging is kept to a minimum, another of the Passivhaus standards.
High Performance Windows And Doors
When most home-owners today replace their windows and doors, they do so with UPVC frames and double glazed windows. To comply with Passivhaus standards, very high-performance windows should be considered including triple glazing. Windows should have a U-value not exceeding 0.8 W/m2K and should also have at least 50% solar hear gain co-efficient, allowing the house to actually reclaim heat from the sun.
Mechanical Ventilation System With Heat Recovery
One of the biggest elements of the Passivhaus ideal is the reduction of energy use for appliances, hot water, space heating and cooling to be less than 120 kWh/m2/year. While insulation, windows and doors are key to this, perhaps the heart of the whole ideal is the MVHR system. This is a single unit that extract air from wet rooms of the property as well as air from outside and uses a heat exchanger inside the unit to temper the filtered air and disperse it into habitable rooms. Up to 85% of heat can be recovered with such a system.
Low Energy Lighting And Energy Efficient Appliances
The final idea is perhaps the easier to incorporate in any home – the use of low energy lighting and energy efficiency appliances. These reduce the amount of energy the home uses and allows it to adhere to the Passivhaus standard.
Making your house Passivhaus or at least getting it closure to the ideal standard is not an easy task and it can cost you a bit extra initially but if you are engaging in a self-build or renovation then it’s something that you really should consider. It will save you money in the long term and this is the sort of standard of architecture that builders will be striving for in the future so why not get ahead of the game.
Stuart Cooke is the Marketing Manager of SpecifiedBy, a product specification platform for self-builders, architects and contractors.
