Sustainable Buildings
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Sustainable building” refers to the economic,
social and environmental impact of buildings and building activities. Over half
of the world’s population lives in urban areas. Houses, factories and offices
in cities, towns and villages have to be heated, lit, cleaned, managed,
maintained, renovated, rebuilt or conserved. Buildings consume. They use energy,
whether for office equipment, televisions or electric lighting, and so burn
fuel, from wood to mined fuel. This contributes to greenhouse gases, while
refrigeration adds to ozone production.
The operation of buildings accounts for 25-40% of
final energy consumption in the urban areas. This is comparable with transport.
And this does not even count the energy consumed for manufacturing building
materials, etc. Construction of buildings and infrastructure could be
responsible for up to half of all material used in some countries. And
then there is the waste that has to be managed and minimised. Safety is another
building concern, as disasters like earthquakes in Japan, Turkey and elsewhere
cruelly remind us. This means setting standards and responsibilities that apply
throughout the buildings’ lifetimes.
Air quality is another building concern and a
health one too. Most people spend as much as 90% of their time indoors. From
birth, through school, work, rest and play, indoor space and air quality is
influenced by buildings and affect our health. This is another good reason why
public policy should seek to influence building norms and objectives, not to
mention reducing the environmental burden.
One problem is that the building sector is
unique. Indeed, it is many things together: water supply, heavy materials,
excavation. And houses have different demands than hospitals, schools or
offices. Buildings are expected to satisfy a wide variety of demands, such as
protection from weather; thermal and noise comfort; safety from fire and other
hazards; supply of quality water, etc. But these demands sometimes contradict
each other. For instance, insulation work to improve heating efficiency in
offices during the oil crisis in the 1970s also led to worsening air quality and
a rise in related health problems from formaldehyde, a chemical found in pressed
wood and insulation foam that causes irritation and dizziness.
Moreover, buildings are fixed capital: the French
call them immobile capital, as distinct from mobile types, like money and
equity. They are a form of investment, vehicles of value and products of
exchange, though fixed in physical space during their entire lifetimes. They are
a key part of the urban engine of capitalism. One problem is that while
buildings can inject value into land, they can also fall apart from negligence,
reducing their own value and that of those around them. Buildings require
maintenance, upgrading or demolition. They can, in short, be a planning
headache.
Clearly, environmental policy instruments that
have been successful in other sectors cannot always be applied to buildings.
Take-back programmes of the type used for beverage containers would probably not
work, for instance. It would be unrealistic to oblige designers or contractors
to take any responsibility for, say, demolition decades ahead. Can we really
know how long a building will last? The Eiffel tower was built a century ago as
a temporary structure for a world fair but still stands robust. The Great
Pyramids have lasted an eternity, but will Pei’s glass pyramids in the Louvre?
Policymakers are starting to pay attention. In
2000, the first international conference on sustainable building (called SB2000)
was held in Maastricht. A second conference (SB2002) will be held in Oslo,
Norway, this September. European housing ministers from east and west held a
“sustainable housing” meeting in Brussels in July.
The OECD is in fact one of the few international
organisations that attempts to look at sustainable building from a policy point
of view, for instance, at how energy efficiency might be improved to reduce cost
and CO2 emissions, or how to reduce material pressure on gravels, sands and
forests, etc. Will this new interest lead anywhere? And will sustainable
development hinder or help the industry? After all, traditionally government
policies aimed to stimulate building as a source of jobs and growth.
Yet, in some ways, the building lobby appears to
be leading the way, in renewable energy installations, for instance. But while
many large-scale contractors are investing in environmental technologies for a
growing market, not so the smaller builders that in fact make up most of the
building trade. These are very slow to adopt new technology and simply insisting
through regulation would either put them out of business or drive them into the
underground economy. That would mean substandard, even dangerous, buildings,
particularly in lower income countries or towns. Therein lies a major public
question: how to spread the technology and know-how that is available and
actually apply it.
Several governments have tried and these
conferences will hopefully help. As ever, there is the question of expense.
Apartment blocks have been built with energy-efficient design, complete with
solar panels and smart technology to control appliances. But their initial cost
has often put them out of reach of all but a well-off few. This may change as
technology costs fall. Already in California, prices of solar-powered houses are
falling fast.
Some concrete examples
Architects can show us the possibilities, but
policymakers can do a lot to promote the adoption of available technologies in
as many building types as possible.
Take environmental labelling for instance. This
may seem like a curious idea for buildings, yet the UK’s Building Research
Establishment has put such schemes in place for new buildings (mainly offices).
It evaluates a wide range of environmental characteristics of buildings. The
scheme is now in use in a quarter of all new office buildings in the UK. Data is
still preliminary, though it suggests that the average energy efficiency of
buildings using it is higher than other buildings.
In 2001 Japan introduced a new voluntary
labelling scheme too, this time for housing. Now, potential buyers can easily
understand which building has which level of energy efficiency. Given Japan’s
earthquake risks, robustness and durability are assessed too. The new scheme has
already been used for more than 70,000 housing units.
Energy auditing is another measure. The Dutch
Energy Performance Advice scheme is a good example of this, aiming to reduce
energy use in existing buildings by some 3 Mt of carbon by 2008-2012. Under the
scheme, technical experts check dwellings and make concrete proposals on
upgrading energy efficiency.
Denmark is perhaps the most advanced country in
this area, with their obligatory Energy Labelling. When someone wishes to sell a
house in Denmark, they must have the efficiency of the house checked and provide
a report to buyers as a condition of sale.
Water-saving initiatives exist too. In the US,
several cities, including New York, introduced new 1.6 gallon per flush toilets
in the 1990s to replace the old 3-5 gallon per flush models. Public authorities
led the drive and some 25 million new units were installed in homes and offices
by the end of the decade. The result has been a sharp drop in water consumption.
A more common initiative is the landfill tax, the
aim this time to encourage better recycling of building materials. Again,
Denmark and the Netherlands are leaders in this area: their recycling rate of
construction and demolition waste has already reached 90%, thanks in part to the
landfill tax. These low-grade recycled materials are not used in building
construction, though, but in road foundations and for landscaping golf courses,
etc. For building construction, technological improvements would be needed to
increase the high- grade recycling such as the use of recycled aggregates in
concrete, and to improve the flow of these goods throughout the sector.
Reference:
OECD (2002), Design of Sustainable Building
Policies, OECD, Paris.
See www.oecd.org/env, under “documentation,
other”.
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