Greenbuild Presenters Encourage Energy
Efficiency in Much-Demanded Glass Buildings
October 7, 2011
By Megan Headley, firstname.lastname@example.org
|Greenbuild featuerd a seminar on
the many products and design techniques available to make today's
glass buildings energy efficient.
"Everyone wants to be in a daylit space these days. When tenants
are looking for a new space, it's all about how much light comes
in," said Eric Duchon of Cushman and Wakefield during his presentation
on "Transparency in the Service of Sustainability: Addressing
the Market Demand for Glass Buildings." Duchon made his presentation
on October 6, the last day of Greenbuild. His comment was based
on an informal survey conducted by the company. The trick for Duchon
and his peers presenting at Greenbuild was convincing their listeners
that using today's technology and careful modeling, glass buildings
can be energy-efficient.
In his survey, Duchon said that he found that energy efficiency
was the most important consideration for any tenants in today's
office buildings. However, he added that most tenants don't seem
to be aware of energy efficiency challenges in glass buildings -
a fact that many architects
point out to their clients.
For John Hannum of Israel Berger & Associates (IBA) the goal
of the presentation was"to show trends and redirect what the
industry perceives as diverging interest in glass buildings and
energy performance. Let's try and get people those glass buildings
that they're used to, that they want, but let's do it better."
Some of the suggestions Hannum offered included using frit patterns
to fine-tune glare issues, considering angling windows - as well
as PV patterns - in the design stage, taking a look at the benefits
of double-skin facades and considering the many options for building
retrofits. He also pointed to up and coming technologies such as
dynamic glazing and products that use a prismatic effect to direct
certain parts of the light spectrum to the areas where it's wanted.
"And finally the frame. How do you address that thermal bridge
which we all know is much more deleterious than the center of glass,"
Hannum asked. One suggestion he offered was getting rid of aluminum
altogether, and replacing it with higher performing structural materials.
William Logan, AIA, with IBA, offered another suggestion. He pointed
out that light shelves and mechanical shading devices can greatly
impact energy savings. "In Europe, triple glazing is becoming
much more common...it hasn't been used here traditionally but you're
hearing much more talk about it."
Logan did caution, "With active facades to really reap the
benefits, it needs to be integrated with lighting, mechanical, etc."
He pointed out the client needs to be considered too.
James Brew of the Rocky Mountain Institute focused on just that.
"Many of you probably know about the top three most common
complaints in buildings," Brew began. He listed: thermal comfort,
glare and acoustics.
Taking these measures into account is a critical part of building
performance, Brew said. "I think when we're thinking about
building performance on the qualitative side [the focus] is the
people. The only measure of a good building is the people who use
Brew pointed to research on the improvements in productivity, reduced
absenteeism and reduced turnover as a result of natural daylighting,
adding that even incremental improvements of that nature should
dwarf the energy-efficiency benefits.
Hannum concluded the presentation with a case study in which he
modeled a glass building on which IBA is working, and set it in
different regions. With light dimming and mechanical shading, he
was able to show significant cost savings in largely glass (75 percent)
You can get to a point where glass buildings have improved productivity,
improved thermal comfort, etc., and still be cost effective, Hannum
explained. "Energy efficiency is achievable for glass buildings,
in other words," he said, but stressed, "Each solution
is building specific.?" It has to be building specific. You
have to focus on the whole building...you have to approach it systematically...and
promote integrity in this analysis."
As the speakers explained, these options have to be explored by
designers - and their design assist partners - because demand remains
strong for glass buildings.
"Glass buildings are where we are now and it's what's going
to continue based on tenant demand," Duchon said.
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