Pass the USGBC Leadership in Energy and Environmental Design (LEED) LEED-AP-BD+C Questions and answers with ValidTests

The surrounding residential density is calculated by dividing the total number of dwelling units by the total residential land area. In this case, it would be 780 dwelling units divided by 60% of 130 acres, which equals approximately 13 dwelling units per acre (or 32 dwelling units per hectare).

The nonresidential density, or Floor Area Ratio (FAR), is calculated by dividing the total nonresidential building floor area by the total nonresidential land area. In this case, it would be 1,600,000 ft² divided by 40% of 130 acres, which equals a FAR of approximately 0.47.

These calculations are used when attempting to achieve the Location and Transportation Credit, Surrounding Density and Diverse Uses, under the LEED AP BD+C V4 rating system.

The Water Efficiency Credit, Indoor Water Use Reduction aims to reduce indoor water consumption by installing water-efficient fixtures and fittings, such as faucets, showerheads, toilets, and urinals1. A commercial dishwasher that is ENERGY STAR® labeled or performance equivalent would help reduce the water use for dishwashing, which is one of the process water uses included in the credit calculation2. A standard garbage disposal would not reduce water use, but rather increase it. An electronic submeter at the domestic water supply pipe to the building would help measure and monitor water use, but not directly reduce it. An open-loop HVAC system that discharges potable cooling water to a nearby lake would waste a lot of water and potentially harm the environment.

According to the U.S. Green Building Council (USGBC) and U.S. Department of Energy, buildings account for approximately 40% of total energy consumption in the United States.

This includes electricity, heating, and cooling loads across residential, commercial, and industrial buildings.

Buildings are the largest energy consumers, surpassing transportation and industry sectors.

LEED emphasizes energy efficiency to help reduce this 40% energy demand.

Buildings account for 40% of all energy consumption, making Option C the correct answer.

(Source: Official LEED BD+C Reference Manual)

Detailed Explanation:

A reduction of 30% in outdoor water use qualifies the project for one point under the Outdoor Water Use Reduction credit, and a 40% reduction in indoor water use qualifies for four points under the Indoor Water Use Reduction credit. LEED awards points for water conservation strategies that significantly reduce the demand for potable water.

Detailed Explanation:

The design charrette is a collaborative, multidisciplinary session aimed at optimizing green strategies throughout the project. This early-phase effort allows stakeholders to explore synergies among building systems, identify sustainability opportunities, and align project goals with LEED requirements. It is a prerequisite for the Integrative Process, fostering holistic design and operational performance improvements.

This is because:

A building automation system (BAS) is a system that controls and monitors various aspects of a building’s operation, such as lighting, heating, ventilation, air conditioning, security, fire alarm, and energy management1.

A BAS can allow programmable load control (PLC), which is the ability to adjust the power consumption of devices or equipment based on a schedule, a sensor, or an event2. PLC can help reduce the energy demand and cost of a building by optimizing the use of resources and avoiding unnecessary or wasteful consumption3.

The LEED AP BD+C V4 credit for Demand Response requires that buildings have a demand response program that can respond to changes in electricity prices or supply by reducing or shifting the demand for electricity4. A BAS can enable such a program by allowing PLC and other features that can modulate the power usage of devices or equipment in response to market signals or internal conditions.

Therefore, installing a BAS to allow PLC can help achieve the Energy and Atmosphere Credit for Demand Response by reducing the energy demand and cost of a building.

A rainwater harvesting system on site could be recognized in the Sustainable Sites Credit, Rainwater Management and the Water Efficiency Credit, Indoor Water Use Reduction. The Sustainable Sites Credit, Rainwater Management rewards projects that reduce runoff volume and improve water quality by replicating the natural hydrology and water balance of the site1. A rainwater harvesting system can help achieve this by capturing and reusing rainwater on site2. The Water Efficiency Credit, Indoor Water Use Reduction rewards projects that reduce indoor water consumption by installing water-efficient fixtures and fittings3. A rainwater harvesting system can help achieve this by providing an alternative source of water for non-potable uses such as toilet flushing and irrigation4.

The other options are not correct. The Water Efficiency Credit, Water Metering does not recognize rainwater harvesting systems, but rather requires projects to install permanent water meters that measure the total potable water use for the building and grounds. The Water Efficiency Prerequisite, Outdoor Water Use Reduction does not recognize rainwater harvesting systems, but rather requires projects to reduce outdoor water consumption by using plant species that are native or adapted to the region and by using irrigation systems that are efficient and properly controlled. The Water Efficiency Prerequisite, Indoor Water Use Reduction does not recognize rainwater harvesting systems, but rather requires projects to reduce indoor water consumption by 20% from the baseline by installing water-efficient fixtures and fittings.

Achieving a minimum of 10 cooling tower cycles by increasing the level of make-up water treatment is the way to obtain the maximum number of points for Water Efficiency Credit, Cooling Tower Water Use. This credit aims to conserve water used for cooling tower equipment by encouraging the use of non-potable water sources and increasing the cycles of concentration1. The cycles of concentration are the ratio of the concentration of dissolved solids in the blowdown water to the concentration of dissolved solids in the make-up water2. Increasing the cycles of concentration reduces the amount of make-up water and blowdown water, and thus saves water and energy2. The credit has two options: Option 1. Non-potable Water Source (1 point) and Option 2. Cooling Tower Water Use (2 points). Option 1 requires using at least 50% non-potable water for cooling tower make-up water1. Option 2 requires achieving a minimum number of cooling tower cycles based on the quality of the make-up water, as specified in Table 1 of the credit requirements1. The maximum number of cycles is 10, which can be achieved by increasing the level of make-up water treatment to meet the criteria for conductivity, silica, and alkalinity1. Therefore, Option 2 is the way to obtain the maximum number of points for this credit. References:

Credit: Cooling tower water use | U.S. Green Building Council

Cooling Tower Evaporation Credits | WaterSignal

Average number of occupants standing or seated

To identify the regularly occupied spaces on a project, the LEED consultant should consider the average number of occupants standing or seated in each space, as this is the criterion used by the LEED Reference Guide for Green Building Design and Construction, 20091. Regularly occupied spaces are defined as areas where workers are seated or standing as they work (or perform regular tasks) inside a building2. The typical duration of occupancy in each space per day is not necessarily relevant, as some spaces may be used intermittently but still qualify as regularly occupied2. The rate of outdoor air provided per person and the fire ratings of installed wall and ceiling assemblies are not related to the definition of regularly occupied spaces, but rather to other credits such as Indoor Environmental Quality or Fire and Life Safety.

The best answer is C. native vegetation. This is because:

•Native vegetation is adapted to the local climate and soil conditions, and therefore requires less water than non-native plants1.

•Native vegetation also supports local biodiversity, reduces erosion, and enhances the aesthetic value of the landscape2.

•Potable water is not a good option for water-efficient landscape design, as it is a scarce and valuable resource that should be conserved for human consumption and hygiene3.

•Sprinkler systems are not a good option for water-efficient landscape design, as they can waste a lot of water through evaporation, runoff, and overspray4. Drip irrigation or micro-sprinklers are more efficient methods of watering plants.

•Permeable pavement is not a good option for water-efficient landscape design, as it is not a plant-based element, but a hardscape feature that allows water to infiltrate into the ground. Permeable pavement can reduce stormwater runoff and pollution, but it does not directly contribute to water conservation in the landscape.