Why build to Passivhaus standard?
The international Passivhaus standard is the world’s leading standard in energy-efficient building design. In this article, Passivhaus designer Es Tresidder of HighlandPassive.com explains why you should consider going for Passivhaus certification for your new-build or retrofit project, and how you should go about it. The Passivhaus standard is well known as an energy-efficiency standard, and it certainly does that well – Passivhaus-certified buildings typically require 90% less heating than existing buildings, or 70% less than typical new-builds (think annual heating bills of around £100 for a 2-3 bedroom house, for the house being warm 24 hours a day). They achieve this through high levels of continuous insulation, high-quality triple glazing, airtight construction and careful design and attention to detail. But Passivhaus buildings offer more than just energy efficiency, they are also more comfortable, more robust and healthier to live in. Here’s how.
More comfortable in winter (and summer)
Passivhaus-standard buildings feel warmer. Walls, roofs and ground floors are better insulated, and the insulation in each element meets the insulation in the other elements with no gaps (thermal bridges). This, coupled with high-quality triple glazed windows, means that the temperatures of the surfaces surrounding you are higher. Warm surfaces mean you lose less heat via radiation and feel warmer. Airtight construction and well-designed ventilation systems eliminate draughts. Well-designed Passivhaus buildings also perform better in summer, staying cooler when the weather gets hot.
More robust
Because Passivhaus buildings are extremely airtight and well ventilated, warm, moisture-laden air does not leak through the building fabric. This eliminates the risk of hidden, long-term moisture problems within the structure of a building.
Healthier to live in
Plentiful fresh air is provided via mechanical ventilation with heat recovery. This means better indoor air quality than naturally ventilated buildings. Better ventilation and warmer surface temperatures mean that mould, which increases the risk of asthma, respiratory infections and allergies, is eliminated. Occupants often remark on an improvement in respiratory health problems, and an improvement in sleep quality.
How do I build myself a Passivhaus?
The easiest way is to work with a certified Passivhaus designer. This could be your architect (some architects are Passivhaus certified), or a designer who helps your architect design to the standards required. The earlier you get the Passivhaus designer involved, the simpler and cheaper it will be – ideally right at the very start of the project, before any of the design work starts. The Highlands and Islands are the coldest, windiest places to build a house in the UK, and we spend a lot of our time indoors escaping the weather. On top of that we have some of the highest fuel and electricity prices in the UK. Here, more than anywhere, Passivhaus makes sense; for your comfort, your wallet, your health and the health of the planet.
Recommended resources
UK Passivhaus trust: http://passivhaustrust.org.uk/ Excellent magazine focussing on Passivhaus: https://passivehouseplus.ie/ Passivhaus blog: https://elrondburrell.com/ Passivhaus-focussed podcast: http://www.houseplanninghelp.com/ Highland Passive website and blog: www.highlandpassive.com