How low can the energy of a building become? The concept of the Passivhaus has put this to the test. A Passivehaus (Passive house in English) are buildings that can maintain constant temperature with minimal heating and cooling. These building are considered the gold standard in energy efficiency because of the way they are designed compared to a conventional building.  They cut the cost of energy bills by up to 90%. If you are interested in buying or renting a low carbon house with low energy bills, it is worth looking for a Passivhaus. Another alternative is If you are interested in making your home as energy efficient as possible and have a big budget, you may want to consider the possibility of changing your house into a Passivhaus. The benefits are that you will have very low energy bills, and it will increase the value of your house.

History of the Passivhaus

The concept of a Passivhaus was developed in Germany when Dr Wolfgang Feist saw a performance gap in conventional housing between predicted energy saving and actual energy use. The Passivhaus Institute came up with the concept of house that is practically self-reliant for its energy needs, with minimal support for heating and cooling. The first one was built in 1991. A Passivhaus has five criteria:

• Thermal bridge design
• Superior windows 
• Ventilation with heat recovery
• Quality insulation
• Airtight construction

A Passive house achieves constant temperatures around the building, from floor to ceiling, so there are no cold spots or hot spots, and this makes them more comfortable. They are good at keeping the outside noise out because they are heavily insulated and have triple-glazed windows.

Passivhaus across the world

The number of Passive houses is growing across the world. There are over 6000 Passive houses across the world, and this has doubled in the last ten years alone. They are being built around the UK by government schemes as part of their strategy to boost new housing. There are a growing number of firms specialising in producing Passive houses and so there is more expertise to help you change your house if you want to go down this route.