PDF LEED-AP-BD+C Study Guide

The assembly U-value of a building envelope component is the overall rate of heat transfer through that component, taking into account the different materials and layers that make up the component. For example, the assembly U-value of a wall would include the effects of the insulation, framing, sheathing, cladding, air films, etc. The assembly U-value is different from the material U-value, which is the rate of heat transfer through a single material. For example, the material U-value of steel is much higher than the material U-value of glass, but the assembly U-value of a steel-framed window may be lower than the assembly U-value of a glass curtain wall, depending on the other factors involved.

References: = [LEED v4: Building Design + Construction Guide], Minimum Energy Performance Calculator - ASHRAE 90.1 - 2010, A Quick and Easy Guide to U-Values - First In Architecture.

The best practice for using alternative water sources is to target the uses that require the least treatment first, such as irrigation, toilet flushing, and cooling tower makeup. This reduces the energy and cost associated with treating water to higher standards than necessary. Matching uses by location is not a requirement, nor is treating all alternative water sources to potable water standards.A project may use more than one alternative water source as long as they meet the applicable codes and standards.References: WE Credit Indoor Water Use Reduction, WE Credit Outdoor Water Use Reduction, WE Credit Cooling Tower Water Use1

An economic advantage of the infill site is that it reduces the need for new utility infrastructure. This is because the infill site is located within an existing urban area that already has access to water, sewer, electricity, and other utilities1. The developer can save on the costs of extending or installing new utility lines and services to the rural greenfield site, which may not have adequate or reliable utility infrastructure2. The other options are not economic advantages, but rather environmental benefits of the infill site. Protecting greenfields and farmland, preserving habitat and natural resources, and reducing potential damage to an existing stream are all positive outcomes of avoiding development on the rural greenfield site, but they do not directly translate into monetary savings for the developer3.

References:

•High-priority site, p. 1

•The Economics of Infill Development, p. 2

•LEED v4 for Building Design and Construction, p. 69

The correct answer is A, site conditions. According to the LEED v4: Building Design + Construction Guide, the Integrative Process Prerequisite, Integrative Project Planning and Design, requires the project team to perform a preliminary “simple box” energy modeling and analysis before the completion of schematic design. The purpose of this analysis is to evaluate the energy performance goals of the project and to identify and compare the energy-related design strategies.The analysis should include the following aspects1:

• Site conditions, such as climate, solar orientation, shading, and natural ventilation potential
• Massing and orientation, such as building shape, size, and orientation, and how they affect the heating and cooling loads, daylight availability, and passive design strategies
• Basic envelope attributes, such as insulation levels, window-to-wall ratio, glazing properties, infiltration rates, and thermal bridging
• Lighting levels, such as the target illumination levels, daylighting potential, and lighting power density
• Plug and process loads, such as the equipment and appliances that consume electricity, and their schedules and controls
• Programmatic and operational parameters, such as the occupancy, operating hours, and zoning of the building
• Thermal comfort ranges, such as the acceptable temperature and humidity levels for the occupants
• HVAC system selection, such as the type, efficiency, and control of the heating, ventilation, and air conditioning system

The other choices are not aspects that should be analyzed when pursuing an integrative design process focusing on energy-related systems, because:

• Potable water availability is related to the water efficiency and water quality goals of the project, not the energy performance goals2.
• Acoustic performance of the project is related to the indoor environmental quality and occupant comfort goals of the project, not the energy performance goals3.
• Applicability of green vehicles to the project is related to the location and transportation and greenhouse gas emissions goals of the project, not the energy performance goals4.

References: LEED v4: Building Design + Construction Guide, Integrative Process Prerequisite, Integrative Project Planning and Design, Option 1.Energy-Related Systems1; LEED v4: Building Design + Construction Guide, Water Efficiency Prerequisite, Indoor Water Use Reduction, Requirements2; LEED v4: Building Design + Construction Guide, Indoor Environmental Quality Prerequisite, Minimum Indoor Air Quality Performance, Requirements3; LEED v4: Building Design + Construction Guide, Location and Transportation Credit, Green Vehicles, Requirements4