CS-2009 SSc7.1: Heat island effect - nonroof 1 point

Our project is a 1.2 million SF science building renovation and expansion for an urban university campus. The program consists of research and teaching laboratories, lab support areas, offices, conference rooms, lecture halls, classrooms, libraries, food service, and public areas. We would like an interpretation on some hardscape materials on our site, dark granite under water and gray concrete. A water feature adjacent to the main entry for this project consists of various waterfalls over granite stone. The granite is dark and does not independently meet the albedo of 0.30. However, running water plays a significant role in lowering not only the adjacent ambient air temperature but also the thermal absorption of the granite. Hypothetically, if the outside air temperature on a sunny day is 100 degrees, then dry granite might be around 110-115 degrees, reflecting considerable heat. However, granite under water would have a lower temperature. The use of water in roof ponds, pools, fountains, cascades, waterfalls, etc. for the purpose of cooling is widely accepted. However, the hard research does not exist for the effect of water on the reflectivity and absorption of granite. If a shaded environment is typically the equivalent of 10 degrees cooler than a non-shaded area, does the water/granite combination appear to be equivalent to a shaded area? Can we include the water feature area SF under the shaded category to factor solar heat reduction into the calculations? We would like a further interpretation with regard to our pedestrian walkways to confirm we can use gray concrete. A 6/27/2003 Ruling states that "for the concrete portion of the site, it is acceptable to use the reflectivity rate for new concrete on this credit, as this will meet the intent of the credit at the time of construction. Reflectance level of applicable materials must be adequately documented to earn this credit." Is it acceptable to use the reflectance documentation from the American Concrete Paving Association, stating that new standard gray Portland cement concrete has a reflectivity between 0.35 and 0.40, to meet the requirements of this credit? Or is an actual ASTM E903 lab test on the actual mix to be used required for the project?

Our project\'s operational requirement mandates large paved areas in excess of 30% of the 490,314 s.f. site area. Our goal is to specify a previously developed concrete mix that complies with ASTM C1549 and has been previously tested and presented to USGBC on a prior project. The test results for this material yielded a Reflectance Average Value of .41 for the concrete paving material. The previous test results on three concrete pavement samples ranged from 0.38 to 0.45 Reflectance (Albedo) Values. The testing lab that conducted the reflectivity testing for the prior project has the following accreditations: IAS-ES TL-189, State of Florida TST 1556, Metro-Dade 01-0727.03, and CRRC. This C.I.R. is requesting confirmation that USGBC will accept documentation certifying that the concrete mix utilized on our project is equivalent to the previously utilized and tested mix and that actual laboratory testing will not be required on a project by project basis.

We are certifying a new manufacturing building on an existing site that currently has a manufacturing building and a parking lot for the staging of tractor truck trailers. Construction of the new manufacturing new building required that the trailer parking lot be relocated to another part of the site. The trailer parking lot relocation was completed before breaking ground for the new building. Would it be appropriate to consider the relocation of this trailer storage parking lot a separate project and to draw our LEED project boundary for the new certified manufacturing building to exclude both the relocated trailer storage area parking lot and the existing manufacturing building? We would use this boundary consistently across all Sustainable Site credits. (SSc5, SSc6 and SSc7)

The credit calls for use of light-colored/high-albedo materials (reflectance of at least 0.3) for 30% of the site\'s non-roof impervious surfaces.We are using a material called UNI Eco-Stone permeable paver that has been tested in Australia at a .27 reflectance value and we are using it for 42% of the non-roof impervious surface. The eco-stone also has a permeability of 12%. We would like to know if we qualify for the reflectivity value of this credit due to the fact that we are using it for more than the recommended 30% of the site\'s non-roof impervious surface. Please advise.

The intent of this credit is to "Reduce heat islands to minimize impact on micro-climate and human and wildlife habitat." The requirements for the credit call for providing any combination of strategies for 50% of the site hardscape. Our project will implement the strategy of using paving materials with an SRI of at least 29. While some of the asphalt areas are shaded within 5 years of occupancy, our proposal aims to achieve the credit using only the SRI-compliant paving strategy. Our project is a major league ballpark in downtown Minneapolis, MN. The LEED project boundary includes the ballpark, the surrounding concrete plaza/walkway areas and an asphalt surface parking lot with shade vegetation and shade from overhead ramps. The total area of hardscaped parking lot, walkways and plaza is 337,456 SF. To comply with the credit requirements, a minimum of 50% or 168,728 SF must have an SRI of 29 or greater. A CIR dated 6/19/2008 for related credit SSc7.2 Heat Island Effect - Roof allowed the use of a weighted average formula where multiple roofing materials were used, such that the total roof area weighted average SRI exceeded the required SRI. Similarly, our project\'s concrete plaza combines standard gray concrete and multiple concrete paver colors into a pattern. While the majority of the pattern is a concrete color with an SRI of 52, a smaller portion of the pattern is a concrete color with an SRI of 12. The parking lot is asphalt pavement, some of which is shaded, but for the purpose of this calculation, we have considered all asphalt to have an SRI of 0. Using the formula for weighted average per the above CIR, we propose performing a similar calculation for each color of all site hardscape to arrive at a weighted average, as follows: [(Area of Asphalt *(SRI of Asphalt/Required SRI)) + (Area of Std. Concrete*(SRI of Std. Concrete/Required SRI) )+ (Area of Concrete Paver 1*(SRI of Concrete Paver 1/Required SRI)) + (Area of Concrete Paver 2*(SRI of Concrete Paver 2 /Required SRI)) + (Area of Concrete Paver 3*(SRI of Concrete Paver 3 /Required SRI))] >= .50 Site Hardscape Area So our calculation would be [(180,672*0/29) + (31,032*35/29) + (97,869*52/29) + (27,883*12/29) = 224,479 which exceeds the 168,728 SF (or 50%) total hardscape requirement. Will this formula be acceptable for SSc7.1 credit compliance?

The intent of this credit is to reduce heat islands to minimize impact on microclimate and human and wildlife habitat. To meet the requirements of this credit we plan to use light-colored/high-albedo materials for a minimum of 30% of the site\'s non-roof impervious surfaces. We have approximately 62,000 SF of white colored gravel driveways on the site, 80,000 SF of asphalt and 38,000 SF of concrete. We have received documentation from the American Concrete Pavement Association stating that new gray portland cement concrete has a reflectivity between 0.35 and 0.40, which meets the requirements of this credit. Aged gray portland cement has a reflectivity between 0.20 and 0.30. Will we be able to use the documentation from the American Concrete Pavement Association as a sufficient source to show compliance with this credit? Also, will we be able to use the reflectivity ranges for new gray portland cement to fulfill the requirements of this credit? We know that black asphalt will not meet the requirements of this credit. We are unable to obtain documentation from the company supplying the gravel on its reflectivity value. We have tried to borrow or purchase a spectrophotometer to measure the reflectivity of the rocks on our own, but have not found an affordable option. We have also tried to find a federal standard on the reflectivity values of different colors and have been unsuccessful. If the rocks are essentially white, will that be enough of an explanation to factor the rocks into the calculation to comply with the requirements for this credit?

The project building maintains 100% of its parking spaces under cover through the use of a multi-level underground parking garage located partially beneath the building and partially beneath the property\'s landscaping and hardscape. In the spirit of SS 7.1, the developer\'s decision to locate 100% of the building\'s parking below grade has resulted in a reduced heat island effect by allowing for surface vegetation where the presence of an above ground garage would have otherwise prohibited vegetation. While it is clear that an uncovered multi-level garage located above ground would have qualified for 1 point under SS 7.1, it is not clear if an underground multi-level garage would qualify for 1 point under SS 7.1 given that it is partially covered by a building with an unknown SRI value. Given that the intent of this point is related to "non-roof" surfaces, is the building required to document SRI criteria for the roof of a building that covers an underground parking garage or is the point otherwise earned automatically since 100% of the parking is located in a multi-level underground garage? Please clarify the intent and required submittals for scenarios involving a multi-level underground parking garage.