EFICACIA Y GARANTISMO EN EL SISTEMA PENAL COLOMBIANO

n Identify all nonroof hardscape surfaces on the project site and sum the total area (T), in square feet. Hardscapes must, at a minimum, include all roads, sidewalks, courtyards, and parking lots within the LEED project boundary.

n Identify all hardscape surfaces shaded by trees or other landscape features (at the time of building occupancy or within 5 years from the date of installation). Shade coverage must be calculated at 10 a.m., 12 noon, and 3 p.m. on the summer solstice. The arithmetic mean of these 3 values will be used as the effective shaded area. Calculated the effective shaded area (S).

n Identify all hardscape surfaces shaded by solar energy panels and sum the total area (E). The shaded area can be considered equivalent to the area covered by the panels on the site plan (from a direct overhead aerial perspective).

n Identify all hardscape surfaces shaded by architectural devices or structures that have an SRI of at least 29 and sum the total area (A). The shaded area can be considered equivalent to the area covered by the architectural devices or structures on the site plan (from a direct overhead aerial perspective).

n Identify all the hardscape surfaces that have an SRI of at least 29 and sum the total area (R).

SRI can be calculated from emissivity and solar reflectance values. Emissivity is calculated according to ASTM E 408 or ASTM C 1371, and solar reflectance is calculated according to ASTM E 903, ASTM E 1918 or ASTM C 1549. Alternatively, use the SRI values for typical paving materials in Table 1 in lieu of obtaining specific emissivity and solar reflectance measurements for the listed materials.

n Identify all hardscape surfaces that have an open-grid paving system that is at least 50%

pervious and sum the total area (O).

n Sum the area of all qualifying surfaces to determine the total qualifying area (Q), using Equation 1.

Each surface should be counted only once. For example, a 10-square-foot area that is 55%

pervious, has an SRI of 30, and is shaded by a tree contributes 10 square feet to the total.

Equation 1

For personal use only and subject to the sales order agreement terms by (BP 10303644). May NOT be copied or distributed.

For personal use only and subject to the sales order agreement terms by (BP 10303644). May NOT be copied or distributed.

Equation 2

Q

>

2

oPtion 2

n Determine the total number of parking spaces within the project boundary.

n Determine the number of parking spaces that are under cover (include underground, under deck, under roof, and under building). This number must be 50% or more of the total number of parking spaces.

The site and building footprint areas used in Option 1 calculations need to be consistent across the following credits:

n SS Credit 5.2: Site Development—Maximize Open Space

n SS Credit 6.1: Stormwater Design—Quantity Control

n SS Credit 6.2: Stormwater Design—Quality Control

n WE Credit 1: Water-Efficient Landscaping

n MR Credit 1: Building Reuse

Similarly, the number of parking spaces used to document compliance with Option 2 needs to be consistent with the requirements of this credit:

n SS Credit 4.4: Alternative Transportation—Parking Capacity 7. Documentation Guidance

As a first step in preparing to complete the LEED-Online documentation requirements, work through the following measures. Refer to LEED-Online for the complete descriptions of all required documentation.

n If surfaces are shaded, prepare a site plan that highlights all nonroof hardscape areas. Clearly label each portion of hardscape that counts toward credit achievement. List information about compliant surfaces (e.g., SRI values of reflective paving materials).

n If parking spaces are placed under cover, determine the total number of spaces and the portion covered. If applicable, assemble SRI values for the roofs that cover parking areas.

8. examples

A building is located on a 25,000-square-foot site, of which 15,000 square feet is occupied by the building footprint and vegetated areas. The project team employs strategies to reduce heat island effect for nonroof surfaces, installing deciduous trees to shade parking and driveway areas and using light-colored concrete with an SRI of 35 for driving aisles and walkways (Figure 1). Areas that contain both light-colored hardscapes and are shaded by trees are counted only once. Table 2 lists the areas of qualifying surfaces.

table 2. sample Qualifying surface areas

Description Area (sf)

total nonroof hardscapes 10,000

shaded areas 3,000

areas of hardscapes with minimum sRi-29 4,000

total qualifying surfaces 7,000

SS

nc credit 7.1

scHooLs credit 7.1

cs credit 7.1

For personal use only and subject to the sales order agreement terms by (BP 10303644). May NOT be copied or distributed.

Figure 1. shading and sRi for credit compliance

Diagram courtesy of oWP/P

9. exemplary performance

Projects may earn an Innovation in Design credit for exemplary performance by demonstrating that either (1) 100% of nonroof impervious surfaces have been constructed with high-albedo or open-grid paving, or will be shaded within 5 years; or (2) 100% of the on-site parking spaces have been located under cover.

10. regional Variations

Heat island intensities depend on weather and climate, proximity to water bodies, and topography.¹⁴ Buildings in very cold climates or at high latitudes may not experience the same rise of surface and ambient temperatures. Buildings in urban areas and those in climate zones 1, 2, and 3 (as defined by ASHRAE 90.1–2007) are most affected by heat islands and are likely to benefit from measures to decrease cooling loads. In sunny climates, project teams should mitigate glare from reflective

SS

nc credit 7.1

scHooLs credit 7.1

cs credit 7.1

For personal use only and subject to the sales order agreement terms by (BP 10303644). May NOT be copied or distributed.

For personal use only and subject to the sales order agreement terms by (BP 10303644). May NOT be copied or distributed.

11. operations and Maintenance Considerations

Surface materials with high reflectivity should be cleaned at least every 2 years to maintain good reflectance.

Some open-grid pavement systems require special maintenance to remain pervious. Request maintenance information from product manufacturers and/or installers and ensure that this information is given to the operations team.

Communicate proper care and maintenance of trees and other vegetation on the project site to landscaping and exterior maintenance crews to help ensure that the anticipated shading is achieved within 5 years.

12. resources

Please see USGBC’s LEED Registered Project Tools (http://www.usgbc.org/projecttools) for additional resources and technical information.

Websites

American Bird Conservancy http://www.abcbirds.org

ABC is a national leader in reducing human effects on birds and wildlife. ABC’s bird collision program supports national efforts to reduce bird mortality through education and advocacy.

American Concrete Pavement Association http://www.pavement.com

This national association represents concrete pavement contractors, cement companies, equipment and material manufacturers, and suppliers. See Albedo: A Measure of Pavement Surface Reflectance, R&T Update (3.05) (June 2002): http://www.pavement.com/Downloads/RT/RT3.05.pdf

Birds and Buildings Forum http://www.birdsandbuildings.org

This Chicago-based non-profit supports bird-friendly design through education and advocacy.

Their website maintains lists of organizations and resources.

Lawrence Berkeley National Laboratory, Heat Island Group http://eetd.lbl.gov/HeatIsland/

Lawrence Berkeley National Laboratory conducts heat island research to find, analyze, and implement solutions to minimize heat island effect. Current research efforts focus on the study and development of more reflective surfaces for roadways and buildings.

New York City Audubon http://www.nycaudubon.org

This Audubon chapter takes a leadership role in reducing bird collisions with buildings. The chapter publishes Bird-Safe Building Guidelines, conducts monitoring, and through its Project Safe Flight, promotes bird-friendly design.

U.S. EPA, Heat Island Effect http://www.epa.gov/heatisland

This site offers basic information about heat island effect, its social and environmental costs, and strategies to minimize its prevalence.

13. Definitions

Emissivity is the ratio of the radiation emitted by a surface to the radiation emitted by a black body at the same temperature.

SS

nc credit 7.1

scHooLs credit 7.1

cs credit 7.1

For personal use only and subject to the sales order agreement terms by (BP 10303644). May NOT be copied or distributed.

Greenhouse gases are relatively transparent to the higher-energy sunlight but trap lower-energy infrared radiation (e.g., carbon dioxide, methane, and CFCs).

Hardscape consists of the inanimate elements of the building landscaping. Examples include pavement, roadways, stone walls, concrete paths and sidewalks, and concrete, brick, and tile patios.

Heat island effect refers to the absorption of heat by hardscapes, such as dark, nonreflective pavement and buildings, and its radiation to surrounding areas. Particularly in urban areas, other sources may include vehicle exhaust, air-conditioners, and street equipment; reduced airflow from tall buildings and narrow streets exacerbates the effect.

Impervious surfaces have a perviousness of less than 50% and promote runoff of water instead of infiltration into the subsurface. Examples include parking lots, roads, sidewalks, and plazas.

Infrared (or thermal) emittance is a parameter between 0 and 1 (or 0% and 100%) that indicates the ability of a material to shed infrared radiation (heat). The wavelength range for this radiant energy is roughly 5 to 40 micrometers. Most building materials (including glass) are opaque in this part of the spectrum and have an emittance of roughly 0.9. Materials such as clean, bare metals are the most important exceptions to the 0.9 rule. Thus clean, untarnished galvanized steel has low emittance, and aluminum roof coatings have intermediate emittance levels.

Open-grid pavement is less than 50% impervious and accommodates vegetation in the open cells.

Perviousness is the percentage of the surface area of a paving system that is open and allows moisture to soak into the ground below.

Solar reflectance, or albedo, is a measure of the ability of a surface material to reflect sunlight—

visible, infrared, and ultraviolet wavelengths—on a scale of 0 to 1. Black paint has a solar reflectance of 0; white paint (titanium dioxide) has a solar reflectance of 1.

The solar reflectance index (SRI) is a measure of a material’s ability to reject solar heat, as shown by a small temperature rise. Standard black (reflectance 0.05, emittance 0.90) is 0 and standard white (reflectance 0.80, emittance 0.90) is 100. For example, a standard black surface has a temperature rise of 90˚F (50˚C) in full sun, and a standard white surface has a temperature rise of 14.6˚F (8.1˚C). Once the maximum temperature rise of a given material has been computed, the SRI can be calculated by interpolating between the values for white and black. Materials with the highest SRI values are the coolest choices for paving. Because of the way SRI is defined, particularly hot materials can even take slightly negative values, and particularly cool materials can even exceed 100. (Lawrence Berkeley National Laboratory Cool Roofing Materials Database)

Undercover parking is underground or under a deck, roof, or building; its hardscape surfaces are shaded.

SS

nc credit 7.1

scHooLs credit 7.1

cs credit 7.1

For personal use only and subject to the sales order agreement terms by (BP 10303644). May NOT be copied or distributed.

For personal use only and subject to the sales order agreement terms by (BP 10303644). May NOT be copied or distributed.

For personal use only and subject to the sales order agreement terms by (BP 10303644). May NOT be copied or distributed.