Green Housing

When walking in heavy traffic among row upon row of buildings in Taipei, seeing displays of public art on avenues lined with trees is a pleasant surprise. New and original buildings in the financial district are even more eye-catching. But more often than not, to green architects the buildings now in vogue are a negative example.

Take Taipei 101, the pride and joy of the people of Taipei, which fails the environmental test miserably, not least because of its great height. Professor Lin Hsien-te of the Department of Architecture of National Cheng Kung University says that Taipei 101 was designed to cater to people's penchant for wealth and rank. Its structure, with a wide top and a narrow base, wastes 30-40% in steel reinforcing beams and is a huge waste in natural resources. In terms of structural mechanics, the new financial building in Chicago will be much more economical and effective, and will save more than 30% in building materials. That's the engineering aesthetics of the future.

Roof pergolas and gardens and insulating bricks are very effective energy saving measures, particularly in a subtropical island such as Taiwan.

Sick-building syndrome

The ubiquitous glass towers of Taipei are substandard in terms of energy saving and healthfulness to their occupants.

"The glass towers so prevalent in Taiwan are incompatible with the humid and hot local climate," Lin Hsien-te says. Glass produces a greenhouse effect. It allows hot shortwave sunlight to penetrate indoors and be converted into long-wave heat energy that is not easily dissipated. This building style is suitable for temperate climates, but here in the subtropics it entails an enormous consumption of power.

To reduce heat absorption, some multistory buildings employ heat-reflecting glass, which produces light pollution. Rogue reflections from glass buildings can blind car drivers and cause accidents. Energy wasteful glass buildings without windows that can be opened are cooled entirely by means of air conditioning, posing an even greater health hazard.

After the 1970s, sick building syndrome (SBS) spread from Europe and America around the world. SBS is caused by the poor quality of the air in buildings with glass facades. Workers in SBS-affected buildings complain of a series of symptoms, including dry throat, eye and nose irritation, headaches, fatigue, cough, and itchy skin. But as soon as they get off work, especially on weekends and holidays, their symptoms taper off or disappear.

In a survey conducted by the Graduate School of Architecture of National Cheng Kung University, 40% of people in Taiwan showed symptoms of SBS and 30% of offices had poor air quality marked by levels of carbon dioxide, airborne microorganisms, and harmful chemicals well above the norms accepted in the United States and Japan.

The Chiang Kai-shek Memorial Hall, a popular attraction for Taipei tourists, fails to meet green building biodiversity standards. Because its decorative lawn flanked by rows of manicured trees hinders symbiosis between insects and the soil, birds don't perch on the trees. Too many gardeners are required to trim the trees, water is wasted, and pollution prevents living organisms from thriving and surviving in this environment.

Lin Hsien-te points out that in Japan many parks are designed as "dense forests" with tall trees and shrubs scattered unevenly across their entire surface area. Fallen leaves are not swept in these parks. In the square in front of the town hall in Cologne, Germany, there is a subway station entrance covered with thistles and thorns which are disliked by commuters but which provide an ideal biotope for insects like earthworms and ants. To retard environmental degradation, building development ought to provide basic habitats that sustain living organisms and small animals.

Living revolution

Taiwan has adopted a green-building labeling system for its subtropical climate, with four evaluation categories (ecology, energy saving, waste reduction, and health) and nine environmental indicators. Taiwan is a pioneer in this area--of the 14 countries that have established such a labeling system, it is the only one in the subtropics. In the past five years, the government has promoted green building, an approach that challenges traditional views in Taiwan's construction industry and the architectural knowledge of society at large.

Waste reduction is a case in point. The construction industry accounts for 29% of Tai-wan's carbon-dioxide emissions, of which 9.3% come from building materials, 1.5% from building transportation, 12% from residential housing, and 6% from businesses. Because every brick and tile in a building can consume a lot of energy and produce pollution, cutting back on unnecessary construction can reduce carbon-dioxide emissions.

Compared to American residential houses made of wood or stone, or to steel framework buildings, the reinforced concrete structures commonly found in Taiwan are very wasteful of energy. Because reinforced concrete consists of 40% gravel from rivers, it is a low-cost material popular with the construction industry and ordinary house buyers. The market for steel framework buildings with low carbon emissions is small, and their cost remains high. "Taiwan's per capita cement consumption is the second highest in the world. In fact, we're all accomplices," Lin Hsien-te says. Ultimately, the huge social cost will be borne by everybody.

Moreover, until recently it was widely felt in Taiwan that a high rate of home ownership was a sign of social stability and prosperity. Added to this is the fact that Taiwanese people's enthusiasm for investing in real estate has resulted in a high level of vacant housing. "We have almost turned buildings into throwaway chopsticks that we dispose of when we're done using them," Lin Hsien-te says. "It's a huge waste." Lin notes that because as houses get old they lose half their value, the quality of building materials is poor, and people don't have a tradition of spending money on taking care of old buildings, the average life span of residential housing in Taiwan is only 45 years, far below Europe and the United States, where the average is over 100 years.

Wide open doors and outdoor passageways awash with electric light are a common sight in Taiwan's department stores. Not surprisingly, their power consumption very high.

A toxic environment

Poor ventilation makes saving energy difficult. What's more, it also endangers people's health.

Chiang Che-ming, director of Department of Architecture of National Cheng Kung University, points out that during assembly or manufacturing processes, all sorts of chemical substances are added to building materials and house furnishings to harden them, bind them together, or protect them against corrosion. As a result of time and temperature such substances are released into the indoor atmosphere in large quantities, causing all sorts of harm to human health. After asbestos was found to cause lung cancer, the World Health Organization also warned that once formaldehyde, commonly used in plywood, carpets and other building materials, reaches a certain level it can also trigger cancer. The most effective way to rid indoor air of toxins is ventilation. The more a room is ventilated, the harder it is for formaldehyde to build up in it.

At the beginning of this year, Professor Jiang Yi, associate dean of Tsinghua University's Department of Architecture in Beijing, was invited to visit Taiwan. He found that most residential buildings in Taiwan are poorly ventilated, and said that installing ceiling fans and air conditioning is pointless. The healthiest solution is to ensure proper ventilation and the exchange of air between the inside and outside of a residence. He also said that we would do well to remember our ancestors' architectural wisdom: good air insulation in winter and plenty of ventilation in summer to minimize heat and humidity.

Healthy buildings

Chiang Che-ming points out that after the green building trend swept the world in the 1990s, health consciousness also began to gain ground. In recent years, this concern has evolved into "architectural preventive medicine." Medical students now have to learn about "healthy buildings" to gain a better understanding of health problems associated with their patients' living environment. Because people spend 90% of their lives indoors, it is important to examine possible root causes of medical problems, such as the building materials of homes and offices, equipment, ventilation, and lighting. Otherwise, patients thought to have been healed can suffer a recurrence of their illness as soon as they return to their old surroundings.

Research on "healthy building" focuses on three main areas: First, the physical characteristics of a building, including climatic influences on them. This includes how a building is integrated into its environment, as well as design features such as ventilation, natural light penetration, shade, and energy saving. Second, chemical properties, namely how to prevent building materials and furnishings from being contaminated with harmful chemical compounds. Third, living organisms, i.e., the contamination of interior living environments with harmful organisms, such as pathogenic molds, avian flu, and SARS.

Chiang Che-ming is concerned that Taiwan's architecture schools have yet to catch onto a key trend of the 21st century: "The sustainable design of the future will not be able to simply satisfy aesthetic expectations, but will have to encompass a wide range of environmental aspects, including light, sound, temperature, air, and electromagnetism."

Fortunately, the Ministry of the Interior, with the full support of the Central Government, has already incorporated seven of the nine environmental indicators that comprise its green building labeling system into Taiwan's building laws and regulations. These will be implemented in stages beginning this year. In the future, all new buildings in Taiwan will be more environmentally friendly.

In other countries, many parks have replaced artificial park management with "natural" management. Unswept fallen leaves look beautiful and are in keeping with the spirit of biodiversity.

Environmental renovation

Many people ask whether only new buildings can be environmentally friendly. What about the environmental renovation of old buildings that are already occupied?

The Ministry of the Interior's Architecture and Building Research Institute (ABRI) recommends reducing our reliance on air conditioning by combining outside shade with good roof insulation.

Outside shade can be created by installing sunscreens and venetian blinds or shutters outside doors and windows. Most Taiwanese houses rely on window curtains for shade. Although curtains are certainly convenient, they don't provide as much protection from the sun as shade on the facade of a building, and they tend to let heat build up and circulate indoors.

Roof insulation refers to all sorts of materials placed on rooftops to effectively protect a building from the heat of the sun, including insulating bricks, roof pergolas and gardens, and airspace in ceilings. ABRI points out that most Taiwanese buildings lack roof insulation. They just have a layer of whitewash and waterproofing. Because rooftops on average get two to three times more exposure to the sun than vertical walls, top-floor residents have to contend with poor quality residential environments and tend to consume too much energy.

To encourage Taiwanese citizens to take the importance of outside shade and roof insulation seriously, since 2002 ABRI has provided financial assistance to NGOs and individual members of the public. Observant citizens will notice that many schools and NGOs throughout Taiwan have already installed outside sunscreens of every description, some of which stand out for their elegance.

Living with less

Using green building materials is also an important way of signaling a commitment to a healthier and more energy-efficient home environment. The Ministry of the Interior issued the "healthy green building material" label a little over a year ago. Chen Jui-lin, director of ABRI's Environmental Control Division, says that during the initial stage the most common building materials, i.e., plywood, paint, rugs, and floor bricks, will be given a label. To avoid exposure to volatile toxins and pollutants, consumers should watch out for the label when buying these products. Once testing equipment is in place, the green building material label will be extended to sofas, cooking utensils, and other household products.

Even without brick-and-mortar improvements, as long as ordinary people adopt green building concepts and make appropriate adjustments in their own lives, residential lifestyles will be much improved. For example, residents can make a point of airing out rooms facing north or south to reduce their habitual reliance on air conditioning. Before going to work, it's a good idea to draw window curtains to let direct sunlight kill germs and to open windows to let in the fresh air.

Professor S.L. Tsai, founder of the Consumer Foundation, takes environmental protection seriously and hasn't bought a single new item of clothing in more than 20 years. Over the years, he has thrown out plenty of old clothes and cleared out his wardrobe. He refuses to buy disposable articles. Thanks to his less-is-more philosophy of life, Tsai doesn't have to worry about a lack of space. To save on air conditioning and electric power, he often reads and writes by daylight. When friends visit him in the evening, they go to a primary school across the street and sit on a stand and enjoy the cool breeze and moon.

Unless humanity hastens to build sustainability, it will face destruction. We cannot afford not to pay for green housing.

Table 1: Power consumption density by building types in Taiwan

Good ventilation and natural light not only help save energy, but are also a good way of getting rid of all sorts of airborne pollutants.

By carefully managing air-conditioning and natural light, the Ambassador Hotel in Hsinchu has cut energy spending from 5.5% of overhead to 3.1% and has been designated an "outstanding energy saving business" by the Ministry of the Interior. The photo shows the roof design of the central lobby, which is fireproof and allows a maximum amount of light to illuminate the building.

The green-building labeling system Taiwan has adopted for its subtropical climate conflicts in many ways with Taiwan's building culture. The photo shows the Yi-Zai Elementary School in Tainan City, which conforms to all nine environmental indicators.