Friday, 6 September 2013

Willful ignorance

I hasten to concede that what I'm about to write may be contributing to the beginning of an urban myth.  But if not, it is a perfect example to support the dominant theme of my blog – that the acquisition of knowledge in architecture is bedeviled by a culture of willful ignorance.

Inhabitat this week carries the story of one more star architect causing havoc with the unintended consequences of his playfully superficial aesthetic concepts.  This time it's Rafael Viñoly’s distinctively curved ‘Walkie Talkie’ building under construction in London, concentrating reflected glare more suitable to solar power station than to an urban building.  Glare from 'Walkie Talkie' Skyscraper Melts Parked Cars in London screams the headline, and one's first inclination is to say 'Yea, right, pull the other leg.'  Until one reads the detail.

It turns out to be pretty simple.The east and west walls of the new skyscraper are prevented by the use of external louvres from causing coherent reflections.  But the north and south facades are left unencumbered by such devices, and deliberately designed with maximum areas of glass to take advantage of the views.The south facade is not only concave in plan but also gently tapered to a subtle curve in section.  From photographs, it appears that the combination is particularly successful in directing specular (mirror-like) reflections from a large part of the facade, in concentrated beams to its surroundings.

While the degree of the problem could be described as novel, the basic causes should be hardly surprising.  I would have thought that any major building in a city like London would have had to submit a reflectivity study as part of its development approval application.

But there is no shortage of precedent of other prominent architects or iconic buildings having experienced similar problems – think Frank Gehry's Disney Hall.  My favourite example is the Vdara Hotel in Las Vegas where concentrated reflections raise poolside temperatures uncomfortably, and undoubtedly shorten the time to an uncomfortable sunburn. That particular case is made all the more interesting by observing not just how the Vdara focuses rays onto its own pool, but also how the reflections from the neighboring Aria Hotel are dispersed outward from its convex surface only to be refocused by the Vdara's concave one.

But let's not get too carried away that this is special knowledge.  Anybody who has ever paid any attention at all to lenses and reflectors, in everyday life, should have been able to predict that some version of this problem was going to be associated with any unobstructed, concave reflective surface.
So which part of everyman's experience is not part of the knowledge base of a famous architectural office?  Because this is not just an issue of a single creative mind wielding a 6B pencil, it is also that the entire team working on this building remained either blissfully unaware or – as I am fond of suggestingwillfully ignorant during months of design development.
In case anyone is in any doubt that we are not talking about trivial little problems, or even the low-grade misery more usually associated with architects getting things wrong, it is worth listening to the video on the Independent newspaper web site here.

The news media make much of melted plastic in cars parked opposite the building, and mention in passing the possibility of blinding glare for motorists.  The popular papers and archipop blogs and zines don't even begin to canvass the additional load on cooling systems of surrounding buildings.  That will happen when the court cases begin – citing all the times and places that this has happened before.  And that is when we will find out that lawyers, unlike architects, do not forget their precedents.

Read more: Glare from 'Walkie Talkie' Skyscraper Melts Parked Cars in London | Inhabitat
More quotes in the Independent, here.

See a video clip case study analysis of solar design problems at the Vdra Hotel, Las Vegas at Gnarly Architecture.  It uses a massing model in Rhino and the Heliotrope plugin with Grasshopper to raytrace solar vectors reflecting off the building surfaces into the swimming pool area.  OK, so I am a bit nerdy, but I want to make the point that architects do have the tools.  Guessing is no longer an option.

3 comments:

Steve King said...

Time to out the cute Easter Egg in the post. I am surprised nobody has commented on it:

The the Vdara Hotel in Las Vegas was also designed by Rafael Viñoly. He even ignored his own experience.

KKK said...

The design of Vdara and ‘Walkie Talkie’ building is an architectural tragedy. It is an abnormal kind of solar design issue in cityscape design, but we know it is possible to prevent it from happening twice.

Since technology has advanced a lot, learning from past experiences can greatly reduce the chance of building design failure. As observed from ’10 Major Architecture Failures’, we notice the causal relationships of the outcomes that have happened .From ‘CNA Centre’, we understand thermal expansion can cause windows to fall. From ‘W.E.B. Du Bois Library’, library books are included as dead load. These examples show us the experiences from the past, yet they are also lessons to be learned and rectify in the present.
The refrain these problems from reoccurring, designs should be thoroughly simulated by utilizing computer programs and calculating the accuracy of the necessary matters beforehand. By doing so, it would maximize the chance to succeed and lessen the risk of failures. Furthermore, designing in a cityscape (high dense) is more complicated than low dense area. It involves a heavier burden of responsibilities as these failures can directly affect the sustainability of urban form (eg. transportation and energy-efficient) in the region and hence to the surrounding population. If one is able to design carefully and thoroughly, it acts as a problem-solving process to avoid small accidents to happen.

References:
CNBC. “10 Major Architecture Failures.” Last modified August 22 2011. Accessed May 3 2014 http://www.cnbc.com/id/44231749. Mike Jenks and Rod Burgess, “Compact Cities: Sustainable Urban Forms for Developing Countries,” (London: Spon Press, 2000), 5. Accessed May 3 2014

XinPei Pei Er said...

Use of glass façade has been rampant nowadays and interestingly enough, it’s a global architectural problem. It is sad that the project team of ‘walkie talkie’ skyscraper did not have full realization of the properties of glass before specifying it on the façade. But, to have the glass façade concaved due to aesthetical purposes, they had just make the matter worse than they could have imagined as the façade will reflect and concentrate sunbeam onto the streets below.

The news of ‘walkie talkie’ skyscraper melting car paint and plastic, is in fact, the more extreme part of our daily problem, whether we realize it or not. Many of us tend to forget that we are now surrounded by a lot of tall modern glass buildings (especially in the city areas) and these glass buildings would at a minimal scale, contribute to the urban heat island effect.
The rise of modernism, influence of Mies Van Der Rohe and also the large manufacturing of glass have in overall, made glass an everyday building material. Glass facades are often used as they open up views to surrounding. Also, they are easy to install, which in turn saves construction time and cost as compared to concrete façade. However, despite its wide usage, many people and professionals don’t seem to understand how glass work, especially from energy efficiency aspect of the building.
Glass is a good transmittance of light and heat, in which it absorbs and emits radiant energy into the building. As a consequence, heat energy is trapped within the building, causing it to function like a greenhouse. Hence, higher energy load is required in cooling the building down. Of course, with our advanced technology nowadays, glass with different properties is widely available in the market, such as glass with different emissivity level or shades and colors. Glass with low-e is widely used as it reflects most of the radiant energy from the façade and allows only certain wavelengths to penetrate through, hence regulating heat gain in the building. However, the setback is that the radiant energy prevented from penetrating into the building is reflected onto its surrounding. Due to the high rise characteristic of a city, it is hard for the radiant heat to dissipate into the surrounding and eventually, the heat is bounced back onto the street level, causing the average temperature to rise- and hence, the urban heat island effect.
Of course, the heat island effect does not depend solely on glass material- it is a problem caused due to a combination of factors such as building heights and materials, including concrete and bricks which absorb and emits heat onto surroundings. However, it is the responsibility of the project team to be mindful of the materials they specify and they should realize that glass should not be a short cut solution to their design problems.
Reference:
1. http://www.dnaindia.com/bangalore/report-glass-in-high-rise-buildings-making-bangalore-hotter-1664782
2. http://www.natureinterface.com/e/ni01/P028-031/
3. http://educationcenter.ppg.com/glasstopics/how_lowe_works.aspx
4. http://epaper.timesofindia.com/Default/Scripting/ArticleWin.asp?From=Archive&Source=Page&Skin=TOINEW&BaseHref=TOIM/2012/01/16&PageLabel=1&EntityId=Ar00105&ViewMode=HTML
5. http://sourceable.net/green-spaces-to-mitigate-urban-heat/