EEWH Green Building Assessment System of Taiwan

Incorporated with Taiwan’s need towards a sustainable built environment described in previous sections, the green building assessment system capable of meeting such a need of Taiwan’s climatic conditions and local environmental issues was initiated in 1998. The system originally comprised of seven evaluation indicators, greenery (vegetation planting), water infiltration and retention, daily energy conservation, water conservation, CO₂ emission reduction, construction waste reduction, and sewage and waste disposal facility improvement. In 2003, due to the increasing interests of health and biodiversity issues globally, the ABRI modified the evaluation system via introducing two additional indicators, Biodiversity and Indoor Environment Quality afterwards. The current assessment system, integrated with nine indicators, was thus finalized.

These indicators can be further divided into four categories, Ecology, Energy Saving, Waste Reduction, and Health (now known as EEWH system), listed in Table 2. In addition to the

assessment tool itself, a Green Building Labeling system for green building certification was also established. The certification consists of two parts: Green Building Label for completed

buildings, and Green Building Candidate Certificate for building projects. The minimum

requirement for green building certification is to pass four indicators, including two prerequisites (energy saving and water conservation) and two optional indicators from among the other seven indicators. The label is valid for three years and renewable. The assessments of the nine

indicators are operated independently in order to reply to the various impacts upon the earth environment, with corresponding quantitative calculation methods, equations, and criteria.

Different from other major green building assessment tools developed by the private sector in the world, such as BREEAM and LEED, the EEWH green building assessment system of Taiwan is

a government initiative and the certifying entity of Green Building Label is the Ministry of the Interior of Taiwan, which has paved a way for further policy implementation and

institutionalization.

Table 2 Evaluation Indicators of Green Building Assessment System of Taiwan Category Indicator Evaluation Items

1.Biodiversity Ecological net, biological habitat, plant diversity (only for the site greater than 1 hectare) 2.Greenery CO2 absorption (kg-CO2/(m².40yr)) Ecology

3.Water infiltration and retention Water contentment of the site

Energy Saving

4.Daily Energy Conservation (prerequisite)

Building envelope design ENVLOAD (20%

higher than building regulation), and other techniques (including HVAC system, lighting, management system)

5.CO2 Emission Reduction CO2 emission of building materials（kg-CO2/m²） Waste

Reduct

ion 6.Construction Waste Reduction Waste of soil, construction, destruction, utilization of recycled materials

7.Indoor Environment Acoustics, Light, and Ventilation, Interior Building Materials

8.Water Conservation (prerequisite)

Water usage (L/person), hygienic instrument with water saving

Health

9.Sewage and waste disposal facility improvement

Sewer plumbing, sanitary condition for garbage gathering

The certification system remained as a pass-or-pass-not mechanism until 2006. According to a green building evaluation review in 2003, a 85 percent of certified green building cases was simply flying over the minimum threshold of green building certification (passing four indicators) with another 9 percent of cases just doing a little bit better (passing five indicators), which

represented a great potential of improving the green building design quality (ABRI, 2004).

Through two years of research, a pilot version of a new green building rating system was launched in 2006 to aim at encouraging better green building design. Its scoring and classification algorithm was developed based on the database of previous green building

evaluation results and existing assessment methods. Following a lognormal distribution (Figure 5), the rating system thus defined five classes of green building design, including Certified, Bronze, Silver, Gold, and Diamond, to encourage better green building practices and innovative design techniques.

Figure 5 The lognormal distribution of previous green building evaluation results formed five classes of Taiwan’s green buildings

The minimum requirement of four-indicator certification described above transferring into the scoring system is 12 points, scoring on a 100 point scale. The building or project receiving the points from 12 to 26 can be classified as Certified. The scores of a Bronze-rated green building will be from 26 to 34, Silver from 34 to 42, Gold from 42 to 53, and Diamond greater than 53.

The weighting factors of each indicator were obtained from an expert survey, listed in Table 3.

The new rating system was officially executed in the beginning of 2007.

Table 3 Weighting Points for Green Building Rating System

Weighting Points Indicator

Minimum Maximum Full Score

1.Biodiversity 2 points 9 points 2.Greenery 2 points 9 points 3.Water Infiltration and Retention 2 points 9 points

27 points

4.Daily Energy Conservation (1) Envelope

(2) HVAC (3) Lighting

2 points 2 points 2 points

12 points 10 points 6 points

28 points

5. CO2 Emission Reduction 2 points 9 points

6. Construction Waste Reduction 2 points 9 points 18 points 7.Indoor Environment 2 points 12 points

8. Water Conservation 2 points 9 points 9. Sewage and Waste Disposal Facility

Improvement 2 points 6 points

27 points

Figure 6 Example of Taiwan’s green building label

The plaque of Taiwan’s green building label is shown in Figure 6. The rating system can also provide a referring basis for further devising policy instruments regarding incentives and stimuli in encouraging a wider adoption of green building in the private sector. Since Taiwan started to promote the design of building energy saving and green building, the condition of high energy consumption and environmental overload has gradually been eliminated. The subtropical and tropical building feature of Taiwan has also been characterized with deep-shading façade, building site layout with more green and permeable spaces, and natural landscape planning. By the end of November 2009, a total of 2,368 buildings or projects were certified as green

buildings with a total floor area of 30.82 million square meters, including 460 green building labels and 1,908 candidate certificates. Based on the latest statistics, from the launch of the rating system in 2007, now there are 13 diamond-rated green buildings, along with 23 gold-rated, 50 silver-rated, 144 bronze-rated, and 779 certified. The percentage of green buildings just passing minimum requirements drops to 77%. In comparisons with the 2003 data, the result indicates a slight progress in enhancing the green building design quality recently.