Leadership in Energy and Environmental Design (LEED) LEED-AP-BD+C Release Date

When calculating the reverberation time of a room, the operating sound level of the nearest HVAC equipment is the least relevant piece of information. The reverberation time is the time it takes for the sound to decay by 60 decibels after the source stops emitting sound. The reverberation time depends on the volume and the surface area of the room, as well as the sound absorption coefficients of the materials that cover the surfaces. The height and width of the room are needed to calculate the volume and the surface area. The noise reduction coefficient of the ceiling surface and the sound absorption coefficient of the floor surface are needed to calculate the total sound absorption of the room. The operating sound level of the nearest HVAC equipment is not relevant for calculating the reverberation time, but it may affect the background noise level and the speech intelligibility in the room.

According to the LEED v4: Building Design + Construction Guide, the location of CO2 sensors in naturally ventilated spaces to comply with the Indoor Environmental Quality Prerequisite, Minimum Indoor Air Quality Performance is between 3 ft. and 6 ft. (1 m and 2 m) above the floor. This is one of the requirements for Option 2. Naturally Ventilated Spaces, which applies to projects that rely on natural ventilation for all or part of the occupied spaces. The CO2 sensors must be located in each zone with natural ventilation openings, and must be capable of generating an alarm when the CO2 concentration exceeds the design value1.

The other choices are not correct, because:

At least 6 ft. (2 m) above the floor is the location of CO2 sensors in mechanically ventilated spaces, not naturally ventilated spaces1.

At least 3 ft. (1 m) away from windows is a general guideline for locating CO2 sensors, but it does not specify the height above the floor2.

On the ceiling 3 ft. (1 m) away from adjacent walls is not a recommended location for CO2 sensors, as it may not reflect the actual CO2 concentration at the breathing zone of the occupants2.

The correct answer is D. Document total waste per building floor area.

According to the LEED v4.1 Reference Guide for Building Design and Construction, Option 2 of the Construction and Demolition Waste Management credit requires projects to reduce the total construction waste generated by the project to less than 12.2 kilograms per square meter (2.5 pounds per square foot) of the building’s floor area1. This option rewards projects for implementing waste prevention strategies, such as designing for material optimization, prefabrication, modular construction, deconstruction, and reuse1. To meet the requirements of this option, projects must document the total weight or volume of all construction waste generated by the project, excluding land-clearing debris and excavated soil, and divide it by the building’s floor area1. Projects must also provide a narrative describing the waste prevention measures taken during design and construction1.

Detailed Explanation:

The combination of alternative water sources (e.g., captured rainwater or reclaimed water) and smart scheduling technology (e.g., weather-based irrigation controllers) is an effective strategy for reducing outdoor water use. These measures exceed the prerequisite requirements and optimize water efficiency by tailoring irrigation to actual landscape needs.