Friday, 17 October 2014

Zombie architecture

Keeping it cool: how Melbourne’s Council House 2 took advantage of the night

That is the headline of a large article in Architecture & Design, on 16 October 2014.

I don't want to poop on their parade, but the article on CH2 repeats uncritically the descriptions of what the building was designed to do, not what the performance actually achieves. In particular, it is a rewrite of the 30 June 2013 post in Archdaily, which was already criticised in its comments for not providing more recent information on achieved performance.

The authors of both articles are either unaware of, or deliberately ignore the study commissioned by the City of Melbourne in 2012, by Paul Bannister of Exergy*.  A long article reporting the study was published in the AIRAH magazine Ecolibrium, and is downloadable by anyone.

The commissioning and design of CH2 was a brave initiative by the City of Melbourne, to explore and provide an example of better performing, healthier commercial office developments. 

At the time in 2002, it was trumpeted that
It was the first new commercial office building in Australia to meet and exceed the six star rating system administered by the Green Building Council of Australia.
Unfortunately, the Exergy study found that the building is achieving far from its claimed best practice performance.  I quote:
1. CH2 is currently performing well below its potential due to the state of the
HVAC controls. It appears that the complexity associated with the building’s
web of relatively unfamiliar sub-systems has led to a range of flawed
strategies and operational issues.

2. The building is an excellent illustation of the importance of optimising
control strategies and commissioning control behaviour for sub-systems, not
only individually but also in their operation as a whole system and under numerous
scenarios.

3. The building is expected to achieve 4.5 stars NABERS base building performance with the measures currently intended for implementation. Further improvement is expected to be realised with intensive monitoring and tuning.
There are other issues with the complex holistic systems implemented at CH2.  They include interesting and subtle effects like a perceptions by staff of gloomy interiors, notwithstanding the thorough modelling that went into the daylight design. There are also particulars of the natural ventilation arrangements at CH2, like toilet smalls introduced into the occupied office space.  These sorts of feedback are known precisely because the Council was interested from the start in studying and reporting on the success of its design initiatives.

Night cooling has potential. No doubt about that. And it is even valid to argue that something like night flushing should be brought to the attention of more designers.  But however well meaning, it is irresponsible to parrot the descriptions of a building from several years ago, from before the effectiveness of those systems had been reviewed.  The commissioned post-occupancy data is much harder to find and to report on than the optimistic claims of the original design team.

Most practitioners will not have the means to 'deconstruct' the rhetorical texts of these articles, more especially if they are dressed up with pseudo-technical spin.  That is how the technical knowledge base of architecture is impoverished, rather than enhanced.
* For those interested in following up on more technical detail, though highly technical, the Paul Bannister article in Ecolibrium is quite readable.  You can download it at
http://www.airah.org.au/imis15_prod/Content_Files/EcoLibrium/2014/March14/03-14-Eco-005.pdf.
I quote from the abstract:
Council House 2 (CH2) is the City of Melbourne’s flagship building for sustainability. The building showcases a number of innovative technologies and has attracted recognition with numerous environmental awards. But how does the building actually perform and what lessons does it have for the broader industry? The City of Melbourne was asking these questions when they invited Exergy to conduct a review of the building’s energy efficiency performance in July 2012.

Exergy’s review focused on the operation of the building’s various systems, including passive chilled beam, tri-generation, thermal storage phase-change material, shower towers and more. Key issues identified mainly pertained to the HVAC commissioning and control strategies applied to these systems not only in isolation, but in the complex web in which they come together.

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