A guide to the passive house standard
If you’re a self builder constructing your property from the ground up and keen to design it as energy efficient as possible, look to the principles of passive house (also known as passivhaus or PH). Originally developed in Germany in the 1980s by Dr Wolfgang Feist, a physicist, and Professor Bo Adamson, a construction expert, the passive house is a low-energy property that maintains comfortable living without compromising architecture or design.
Here, we delve deeper into the principles, benefits, strategies, performance targets and common challenges, and certification process associated with the Passive House Standard.
What is passive house?
Providing a tea-cosy-like shell for buildings, the passive house system provides an air-tight, high-performing insulated exterior for properties. This means that the passive house focuses almost entirely on the energy the building uses, reducing extensive heat loss.
The Swedish/German concept is underpinned by five guiding principles: airtightness, thermal insulation, mechanical-ventilation heat recovery, high-performance glazing (including windows and doors), and thermal-bridge free construction. Taken together, the guiding principles meet the rigorous requirements of the International Passive House Association.
Passive House design is driven by air quality and comfort. The Passivehaus Institute states ‘a passivehaus is a building in which thermal comfort can be achieved solely by post-heating or post-cooling the fresh air flow required for a good indoor air quality, without the need for additional recirculation of air.’
What are the benefits of passive house?
Thousands of buildings have been certified to the passive house standard worldwide. The benefits are plentiful:
Boosts energy efficiency
Energy needed to heat a passive house is 90% lower than that of a standard home – there’s no allowance for traditional heating and cooling systems like boilers and air conditioning. According to Passivhaus Trust UK, this achieves a 75% reduction in space heating requirements, compared to standard practice for UK new build.
Year-round even temperature
Temperatures are kept consistent from room to room in both summer and winter, without the need for additional heating or cooling systems. This even temperature creates a comfortable, consistent indoor climate, shooing away pesky drafts entirely. What’s more, the high-quality insulation also reduces noise, creating a more peaceful environment.
Cleaner, filtered air
These builds also achieve extremely high-quality indoor air. Conventional buildings are not airtight, meaning toxins and particulates from passing traffic, for example, can get into the building and circulate. Thanks to their tight envelopes, the air in a passive house is only ever exchanged for fresh, filtered air. Of course, the bonus of this is less time spent cleaning – so this type of home is beneficial to people with allergies or sensitivities to mould or mildew.
Long-term cost savings
Environmental journalist Lucy Siegle describes future savings that can be made building to passive house standards, stating: “Long term, you can live in year-round thermal comfort for the cost of running a hair dryer.”
Reduced greenhouse gas emissions
A passive house greatly contributes to the nationwide move to protect the environment, having a significantly lower carbon footprint compared to traditional buildings. It uses only natural energy from the sun, reducing greenhouse gas emissions and making it a more ethical choice for greener living.
How to achieve the passive house standard
Getting the passive house badge of approval takes a lot of careful planning, design, and construction. Your build must be certified by the Passivehaus Institute or an authorised UK company and must incorporate the key passive house principles to ensure stable air temperatures, comfortable indoor air, and minimal energy use. The main principles are:
Extremely high levels of insulation
Arguably, this principle is the most important. High-quality insulation will minimise heat exchange with the outside environment, so building design must prioritise the quality of the insulation – the two go hand in hand.
No thermal bridges
The way high-quality insulation is installed matters. Maximum insulation can be achieved with a ‘blanket’ used in the ceilings, floor, and walls - this should have no gaps (or thermal bridges) that interrupt the insulation. Ensuring this means there’s less of a need for additional heating or cooling to reach a comfortable temperature.
Airtight construction
No draughts in, no leaks out - the structure must be airtight to limit heat escape and reduce energy costs. Fabrics and materials should be carefully considered at the design stage to ensure the ‘skin’ of the building is continuous and clear.
High-efficiency windows and doors
Thermally speaking, windows and doors have to be twice as good as conventional new windows and doors, demonstrating extremely high performance with insulated frames. For windows, this typically means triple glazing, and can include non-conductive framing or warm-edge spaces. In order to minimise heat loss, provide insulation, and block out noise pollution, doors also need designing and crafting to passive house standards. All Deuren doors can be made to these technically superior standards.
Mechanical ventilation with heat recovery
Once the building is air-tight, a high-quality mechanical ventilation heat recovery (MVHR) system needs to be implemented in order to flush out stale air and replace it with fresh, filtered, temperature controlled air.
Challenges to achieving passive house standards
While passive house buildings are crucial in a climate emergency, and deliver ultra-high standards of comfort and health, passing these standards comes with various challenges. Passivehaus research says meeting the standards can add 8-10% to the price of a new build. However, there are affordable passive house schemes in Europe, and the long-term energy savings can offset these costs. Retrofitting an existing home with passive house strategies can also reduce energy use by 75%.
Deuren and passive house standards
If you’re embarking on a build project and require its design to be as efficient as possible, all Deuren front doors can be made to passive house standards. They’re specified in Thermal, Thermal 1, and Thermal 2 configurations and work hard to minimise heat loss and provide super insulation. Where a standard door would have a U Value of 1.2, Deuren can help you meet passive house standards by manufacturing your doors to achieve a U Value 0.6. If your doors require glazed panels, we can triple or quadruple the glazing to add to the thermal qualities of the door and block out noise pollution.
If you’re looking for inspiration for a passive house project and need expert advice about your door requirements, book an appointment to visit our showroom and factory.