What is Passivhaus? Architect, Associate & Qualified Passivhaus Designer Andrew Walters explains…
‘Passivhaus’ – or ‘Passive House’ – by definition is a set of standards developed and stewarded by the Passivhaus Institute. Developed in Germany in 1990, the Passivhaus design standard provides the blueprint for energy efficient building principles, and has become an embedded solution to why low energy buildings didn’t deliver on their potential.
The Passivhaus standard provides a range of proven approaches to deliver net-zero-ready new and existing buildings optimised for a decarbonised grid and improved for occupant health and wellbeing, providing a high level of occupant comfort using very little energy for heating and cooling.
To achieve Passivhaus certification, a project must use the specific Passivhaus system which facilitates projects to deliver upon the design targets of the standard. Applicable projects are required to apply to the Passivhaus Institute for the scheme to be certified.
Our qualified Passivhaus Designer, Andrew Walters – who completed the complex exam and testing to develop his skills in accurate design modelling using the Passivehaus Planning Package (PHPP) – explains that there are 5 principles of creating a Passivhaus which differ to a normal well-built house.
So, what are the principles?
To achieve the Passivhaus Standard in the UK typically involves:
- Superinsulation: very high levels of insulation in walls, roofs and floors to minimise heat loss
- High-Performance Windows: commonly triple-glazed to maximise solar gain whilst minimising heat loss, with insulated frames
- Airtight Building Fabric: extremely airtight construction, reducing drafts and heat loss
- Heat Recovery Ventilation: a mechanical ventilation system with highly efficient heat recovery to ensure fresh air without losing heat
- Thermal Bridge Free Construction: to minimise or eliminate thermal bridges in the building envelope
Whilst all these items are not exclusive to a well-built house, the combination of such items and the rigorous review against the energy targets are what make a Passivhaus.
Over the last few years, HPA have experienced an increase in clients requesting Passivhaus, but often the dependency on mechanical ventilation has been a detracting factor. However, developments in technology and more awareness are driving demand, with funders and developers seeing the standard as the gold star in quality.
One such project designed by HPA and currently under construction is an innovative house build project in picturesque Silverdale. The plan was to transform an old concrete block structure into a modern, energy-efficient family home that aligns with Passivhaus principles. Our client’s vision was to create a home of exceptional quality that is also self-sufficient. The design incorporates sustainable water and electricity sources to ensure long-term energy efficiency and minimal environmental impact.
The project includes several special design features: a solar photovoltaic roof to harness solar energy, greywater recycling to efficiently reuse water, and roof lights and full-height glazing to maximize natural light throughout the home. The exterior will combine vertical and horizontal timber cladding with coursed random stone for a striking aesthetic. Inside, the home will feature an open plan living, kitchen, and dining area with a central double-height space over the dining table.
This trailblazing scheme promises to be a model of modern, sustainable living, blending innovative design with environmental consciousness to create a home that is both beautiful and functional, closely aligned with the Passivhaus principles.
Contact Associate, Architect & Qualified Passivhaus Designer Andrew Walters at HPA Architects to develop your Passivhaus project; offering support and solutions for improving sustainability and reducing the environmental impact of your project, together with our sister company www.woohoo.ltd
