1. the quality of being honest and having strong moral principles.
2.the state of being whole and undivided.

Breaking promises damages your integrity. Do you make promises about the performance of buildings you design or construct? And do your buildings keep those promises?

Let me share a short story with you.

On a commission where I was the project architect, we reassured our clients that their new building would be super energy efficient, among other things. And yet, once the building had been handed over, I found myself in an embarrassing situation.

In a meeting with the clients, they put me on the spot and asked me why the energy bills were so high. No matter how many times I explained that the new building was much larger than their old building and had a lot more energy consuming equipment in it, there was no way out: in the clients’ mind we had not delivered on the promise of a super energy efficient building.

In fact, the new building was very energy efficient. However, we had never quantified what we meant by a “super energy efficient” new building. Therefore, the clients’ interpretation of this was lower energy bills and all they had to compare were the energy bills from their old building.

Needless to say, this project wasn’t a certified passivhaus building. Had it been, we could have given the clients an accurate prediction of what the (radically low) energy consumption would be. They would have had a good estimate of the expected energy bills. And the building would have performed as predicted. Our promise would have been kept.

Integrity is a reason to Love Passivhaus!

018 Love Passivhaus Integrity

Love Passivhaus: Integrity of Defined Outcomes

An important aspect of the Passivhaus Standard are the clearly defined performance requirements for certification. With passivhaus, unlike most other green building standards, you know what outcomes you are being promised. Different aspects of the standard can’t be played off against each other, compromising the outcomes. Getting a passivhaus building is like getting a new car: the performance is clear upfront.

Some of the specific requirements of the Passivhaus Standard are:

  • Heating: Specific space heating demand ≤ 15 kWh/(m2a)
  • Primary Energy: Specific primary energy demand for heating, cooling, hot water, auxiliary electricity, domestic and common area electricity ≤ 120 kWh/(m2a)
  • Airtightness: Pressure test result, n50 ≤0.6 h-1
  • Modelling: Building energy model completed in the Passive House Planning Package (PHPP)

Meeting these stringent requirements ensures that excellent indoor comfort can be delivered along with radical energy efficiency. And the clarity of these defined outcomes quantify what radical energy efficiency and excellent comfort mean in real numbers.

There is no confusion or vagaries about what is necessary to achieve the Passivhaus Standard. Everyone on the team knows what they are working towards. The clients know what they are being promised.

With passivhaus, integrity of defined outcomes means you know what performance you’ll get.

Love Passivhaus: Integrity of Performance (No Gap!)

With passivhaus, no only is the performance clear, it is reliable. Buildings certified to the Passivhaus Standard, on average, consistently perform as predicted, or better. The so-called ‘performance gap’, widely acknowledged as a significant issue in the construction industry, is eliminated.

Of course, building performance and energy consumption varies according to how people use a building. However, the building design and construction determines the magnitude of influence occupant behaviour can have on the performance. Crucially, the Passivhaus Standard reduces energy consumption to such a degree that even ‘profligate’ energy consumption by occupants doesn’t result in a huge difference in performance. Doubling, or even tripling, of ‘very little’, is still ‘very little’! And since passivhaus buildings provide excellent comfort conditions, people need not consume excessive energy, battling against the discomfort of draughts and cold surfaces.

This graph on passipedia provides an excellent illustration of the performance of passivhaus buildings and the range of occupant influence. Note that even the most ‘profligate’ consumer of energy in a passivhaus building is still using less energy than ‘best behaved’ occupants in a German ‘low energy’ building. (And noting that a German ‘low energy’ building is still incredibly energy efficient.)

So how does the Passivhaus Standard achieve such integrity of performance?

Firstly, the Passivhaus Standard is designed with this intention. The standard came out of research into why ‘low energy’ buildings weren’t performing as well as predicted – that is, the performance gap – and why they weren’t as comfortable as intended. The research identified where the problems were and ensured that the standard specifically took care of these aspects of building physics and quality assurance.

Secondly, the Passivhaus Standard requires the use of the Passive House Planning Package (PHPP). This is very detailed and highly accurate energy modelling spreadsheet. PHPP was built on the foundation of the research mentioned above specifically to assist in delivering buildings to the Passivhaus Standard. And it is focussed very carefully on the aspects and elements of design that actually matter for building performance. It is a design tool that ensures a building will perform as intended.

With passivhaus, integrity of performance means you get what’s promised

Love Integrity: Love Passivhaus

There is integrity in the clarity and simplicity of the Passivhaus Standard performance requirements. And for a building to be certified to the Passivhaus Standard it must meet all the requirements. There is no mistaking the radical energy efficiency and excellent comfort that passivhaus buildings provide.

The Passivhaus Standard has integrity of delivered performance, eliminating any performance gap. The rigour and thoroughness of the standard takes care of all the critical elements of building performance to ensure this. And passivhaus buildings must be modelling with the PHPP tool that integrates reliable accurate building performance into the design process.

The Passivhaus Standard provides integrity of defined outcomes and integrity of performance. You know what you are getting and you know can count on the promises it makes. Architecture in the anthropocene needs to deliver radically energy efficient buildings. And buildings need to perform as intended; good intentions aren’t enough. The world needs more passivhaus buildings.

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.