What information is needed to determine if a product will help with the heat isl

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试卷: LEED GA模拟题D[查看]
What information is needed to determine if a product will help with the heat island effect of a non-roof surface?
A: SRI of the material
B: Run-off coefficients for the material
C: Emissivity of material
D: Life cycle costs of the material

参考答案: A

本题解释:
Notes:

Reference: LEED for Existing Buildings: Operations & Maintenance Reference Guide, Glossary

The heat island effect is created when developed areas have higher temperatures than surrounding rural areas. An urban heat island effect is caused by sunlight heating up dark colored surfaces such as roads and rooftops. Huge quantities of heat are generated in buildings that have dark rooftops and absorb heat rather than reflect it.

Solar Reflectance Index (SRI) indicates a material\'s ability to reject solar heat and is the combined value of reflectivity and emittance. Measurements vary from 100 (standard white surface, most reflective) to 0 (standard black surface, least reflective). Materials with the highest SRI values are the coolest choices for paving.

Many outdoor materials now come with the SRI value printed on the label so purchasers know how the product will impact the urban heat island effect. The higher the SRI number the more solar heat the material can reflect. Black asphalt has an SRI of 0.

B:Run-off coefficients are used for stormwater management.
C:Project teams do not need the emittance of a material. They do need the SRI value because that is what is needed for the LEED credits. The emittance of a material refers to its ability to release absorbed heat. Scientists use a number between 0 and 1, or 0% and 100%, to express emittance. With the exception of metals, most construction materials have emittances above 0.85 (85%). Emittance is used by manufacturers to calculate the SRI.
D:The life cycle cost does not indicate if the material will reduce heat islands.