Passive houses are a German design but can have a British location with a tropical climate, how is this possible? Because PassivHaus’ are super efficient and their construction makes for warmer homes which translates into lower energy bills for the homeowner. Sounds too good to be true doesn’t it. So if a PassivHaus offers this why aren’t all new builds built this way?
Passive houses, as they are known in the UK, were designed in Germany in the 1990’s by the PassivHaus Institute. Since then more than 30,000 homes, schools and offices have been built to their standard, although most of the builds have been in Germany and Austria. One of the first certified PassivHaus’ in the UK was a three bedroom house in Denby Dale,Yorkshire and was completed in May 2010.The owner of the house says that it is as easy to run as any house as the technology is in the building of it.The PassivHaus is ideal for new builds as the high levels of energy efficiency are embedded into the house when it is being built. The end product is a house which uses 90% less energy than a standard house. The owners admit that the only big difference between their house and a normal one is the bills.
The first gas bill that the couple had for the house wasjust £26 for the quarter and the electric bill was even lower at £17. Compare these bills to the couple’s last oneswhen they lived in a 300year old terraced house where their bills were £1,800 ayear and you can really notice the difference, as the owner said the differencewas “phenomenal”.
So what sets a Passive House apart from a typical eco-house which is becoming popular now? A PassiveHouse has no obvious green giveaways as it is the invisible components of the house that make it green. A PassivHausworks like a tea cosy, wrapping the house in continuous insulation rather than just the loft and walls. The company also insists on stringent levels of air tightness to create minimal thermal bridging or “the tea cosy effect”. Like other eco houses a PassivHaus is designed to optimise the heat generated from the sun and they also have a MVHR system installed. This system provides the house with fresh air and helps to warm it by recovering heat from the extracted air and transferring it to the incoming air. Heat from inside the house, generated from humans or cooking etc..is then retained within the building. Therefore this means that the house needs very little heating or air conditioning.
The owner of the house said that when the house was being built he visited it at night, it was -14C in the garden but the house was10C. The Denby Dale PassivHaus is a pioneering project as there was, at the time, nothing similar in the UK. They visited ones in Austria instead and found them modern and light. It ispossible to import them from Germany but builders over here are not familiar with erecting them and planning can be an issue. So the house was built locally with the stone from the builder’s yard up the road and this house has cavity walls so it is like a traditional British house but with a Passive twist. The budget was £141,000, which proves those eco houses are not just for the wealthy.They have been tried and tested for twenty years and have proven methodology in achieving low energy buildings.