Architectural design is typically carried out with little or no environmental consideration integral to the process. Once the design has reached a certain stage environmental considerations – whether material toxicity, water conservation, carbon emissions or energy conservation or something else – are then assessed. At this point decisions are made to revise and iterate the design for better environmental outcomes or to add ‘environmental features’. We know the results of this disjointed design process and we know this has to change if buildings are going to be better for people and the planet!
Unfortunately many environmental standards reinforce this process in two ways. Firstly by being separate from the design process, often as an assessment procedure. Secondly by requiring ‘environmental features’ be added in order to score points or increase the rating of the design.
The Passivhaus Standard is different. Unlike most environmental standards for architecture, design is central to the Passivhaus Standard. And the Passivhaus Standard is central to the design process.
Design is a reason to Love Passivhaus!
Love Passivhaus: Design at the Macro Scale
Determining the orientation of a building is a critical part of the design process – for urban and spatial relationships, for landscape and topographical relationships and for views from the building and of the building. Orientation also matters for passivhaus design, as I wrote about before. The orientation of a building imposes solar gain and heat loss constraints on the building that will impact on the building performance.
Form, shape and massing are all important architectural aspects of building design. These can determine the look, feel and impression of a building. They also play crucial roles in determining the performance of a building. For example, if the ratio of external surface area to internal volume is too high, greater insulation performance is required to keep the heat in (or out). Compact forms are inherently energy efficient.
Sizing and shaping transparent elements, whether windows and doors or curtain walling, play an important part in the architectural design process. Transparent elements all impact on the feel and appearance of a building, the rhythm of the façades, the architectural style and many more aspects. Similarly they are absolutely crucial to the performance of a building – too much in the wrong locations causes problems, too little in the wrong places also causes problems.
And the choice of materials that make up the very fabric of the architecture – the walls, floors and roofs – can result in completely different buildings. From the structure and insulation type through to the external cladding, the fabric is integral to the architecture. Similarly these choices and the resulting performance will play a significant part in determining if a building will meet the Passivhaus Standard or not. It is a ‘fabric-first’ standard: it isn’t possible to design a building with fabric that performs poorly and then add on some ‘environmental features’ to meet the standard.
For passivhaus, the architecture counts: design is crucial.
Love Passivhaus: Design at the Micro Scale
Architects and building designers are often taught that a design concept should be consistent from the form of the building right down to the construction details. Or as often quoted:
God is in the details
– Ludwig Mies van der Rohe
Another way of considering this is that design integrity is in the details – the construction details of how a building is put together and the finished details where people interact with the building.
This is true of poetic metaphors that architects dream up and hope occupants and visitors to the building will grasp and appreciate. A big ‘architectural’ idea for a building falls flat when a minor handrail detail, for example, clashes with our aesthetic sensibilities or is plain impractical. It is also true for building performance and passivhaus. While the macro design elements discussed above can set the possible performance range for a building, it is the details that produce the specific performance.
Layering of materials within construction assemblies along with junctions between elements and components all impact the integrity of a concept or metaphor. They all impact our experience and interaction with a building at a human scale.
These details also all impact on insulation performance and continuity (that is, elimination of thermal bridging), airtightness and moisture protection. These details all affect the energy consumption of a building. And importantly they are key to delivering the comfort of a building – warmth, draught-free spaces, fresh air, no radiant cold surfaces – all hallmarks of passivhaus buildings.
For passivhaus, the details counts: design is crucial.
Love Design: Love Passivhaus
I write this blog post as an architect and therefore I’ve set out aspects of the design process that I am familiar with. However, the same integral relationship between design and passivhaus exists for structural engineers and for building services engineers. And for other designers involved in delivering passivhaus buildings.
And remember, the Passive House Planning Package (PHPP) is a design tool, not a static assessment tool. While it is also used for quality assurance and for certification, it is an open and parametric design tool. It is best used from the very beginning of the design process and as an integral and iterative part of the design process, alongside detailed knowledge and understanding of passivhaus and how buildings perform.
Design is central to the Passivhaus Standard and the standard is central to the design of radically energy efficient and exceptionally comfortable buildings. This is the type of architecture that the world needs in the anthropocene.
This blog post is part of a series of posts on reasons to love the Passivhaus Standard – in contrast to the tongue-in-cheek post ‘10 Things I Hate About Passivhaus‘ which you may have already read. The #LovePH series was prompted by the inaugural South Pacific Passive House Conference and Trade Show taking place in Auckland, New Zealand, over Valentines weekend 2015. I was privileged, both as a Kiwi expat and as a passivhaus architect and enthusiast, to be invited to give a presentation at the conference, on behalf of Architype Ltd where I work.
Please join in and share on social media what you love about the Passivhaus Standard using the hashtag #LovePH.
And for more posts on reasons to ‘Love Passivhaus’ and other passivhaus related topics, please subscribe by email at this link.