Getting Started

How to use this Reference Guide

This reference guide is designed to elaborate upon and work in conjunction with the rating system. Written by expert users of LEED, it serves as a roadmap, describing the steps for meeting and documenting credit requirements and offering advice on best practices.

Within each section, information is organized to flow from general guidance to more specific tips and finally to supporting references and other information. Sections have been designed with a parallel structure to support way finding and minimize repetition.

Each credit category begins with an overview that discusses sustainability and market factors specific to the category. For each prerequisite and credit, readers will then find the following sections:

• Intent & Requirements outlines the rating system requirements for achieving the prerequisite or credit. They were approved through the rating system development process and can also be found on the USGBC website.
• Behind the Intent connects credit achievement with larger sustainability issues and provides information on how the credit requirements meet the intent stated in the rating system.
• Step-by-Step Guidance suggests the implementation and documentation steps that can be used by most projects, as well as generally applicable tips and examples.
• Further Explanation provides guidance for lengthy calculations or for special project situations, such as tips for nonstandard project types or different credit approaches. It includes a Campus section and, sometimes, an International Tips section.
• Required Documentation lists the items that must be submitted for certification review.
• Related Credit Tips identifies other credits that may affect a project team's decisions and strategies for the credit in question; the relationships between credits may imply synergies or trade-offs.
• Changes from LEED 2009 is a quick reference of changes from the previous version of LEED.
• Referenced Standards lists the technical standards related to the credit and offers weblinks to find them.
• Exemplary Performance identifies the threshold that must be met to earn an exemplary performance point, if available.
• Definitions gives the meaning of terms used in the credit.

More about the Further Explanation section

Further Explanation contains varied subsections depending on the credit; two of the common subsections are elaborated upon here.

Campus Projects

Campus refers to the Campus Program for Projects on a Shared Site, which certifies multiple buildings located on one site and under the control of a single entity. Examples include buildings on a corporate or educational campus and structures in a commercial development. Only project teams using the Campus Program need to follow the guidance in the Campus section; the guidance is not applicable to projects that are in a campus setting or are part of a multitenant complex but not pursuing certification using the Campus Program.

There are two approaches to certifying multiple buildings under the Campus Program:

• Group Approach allows buildings that are substantially similar and are in a single location to certify as one project that shares a single certification.
• Campus Approach allows buildings that share a single location and site attributes to achieve separate LEED certification for each project, building space, or group on the master site.

For each approach, the reference guide gives any credit-specific information and notes two possible scenarios:

• Group Approach
  • “All buildings in the group may be documented as one.” The buildings may meet the credit requirements as a single group by, for example, pooling resources or purchasing, and then submitting a single set of documentation.
  • “Submit separate documentation for each building.” Each building in the group project must meet the credit requirements individually for the project to earn the credit.
• Campus Approach
  • “Eligible.” This credit may be documented once at the level of the master site, and then individual projects within the master site boundary earn the credit without submitting additional documentation.
  • “Ineligible. Each LEED project may pursue the credit individually.” Each project within the campus boundary may earn the credit but each project must document compliance separately.

Projects Outside the U.S.

The International Tips section offers advice on determining equivalency to U.S. standards or using non-U.S. standards referenced in the rating system. It is meant to complement, not replace, the other sections of the credit. Helpful advice for projects outside the U.S. may also appear in the Step-by-Step Guidance section of each credit. When no tips are needed or available, the International Tips heading does not appear.

Units of measurement are given in both Inch-Pound (IP) and International System of Units (SI). IP refers to the system of measurements based on the inch, pound, and gallon, historically derived from the English system and commonly used in the U.S. SI is the modern metric system used in most other parts of the world and defined by the General Conference on Weights and Measures.

Where “local equivalent” is specified, it means an alternative to a LEED referenced standard that is specific to a project’s locality. This standard must be widely used and accepted by industry experts and when applied, must meet the credit’s intent leading to similar or better outcomes.

Where “USGBC-approved local equivalent” is specified, it means a local standard deemed equivalent to the listed standard by the U.S. Green Building Council through its process for establishing non-U.S. equivalencies in LEED.

Taking an Integrative Approach to Operations and Management

To meet human needs without compromising the bottom line, green building operations require dedication and buy-in from all levels of building and tenant management. The path to sustainable operations requires collaboration, integrative thinking, and a strong team whose members have clearly defined roles and responsibilities.

Successful operations practice engages all team members and emphasizes each person’s responsibility for continuing sustainable strategies during transitions and change-over periods. It requires collaborative decision making and information sharing by everyone involved, including staff who oversee waste, chemical applications, or product purchases.

As the team is drafting and implementing a new building policy, for example, an approach that draws on the expertise of all project stakeholders—owner, occupant, engineers, facilities managers, financial managers, contractor—may reveal innovative solutions.

Project Goals

An integrated team can develop project goals that lay a strong foundation for achievement. The project goals should reflect organizational values and operational realities as well as sustainability targets. Include building stakeholders who understand current facilities practices, such as the owner, building management staff, occupants, and vendors. A diverse team ensures that all operational elements will be considered and the program will be supported by the entire team.

Take a hard look at traditional practices and management and consider the flow of materials, water, and energy through the building and site. For existing buildings, this requires a site study that considers on-site resources and the building’s location, orientation, massing, and occupant use patterns. The goal is to identify ways to reduce the loads and environmental harms of each system without increasing those of any others.

Identify existing policies, practices, equipment, contracts, and budgets to set a baseline for improvement. After collecting baseline information, list the areas that may require significant change, moderate change, and low- or no-cost change in operating practices. Identify any organizational issues or pressures that may influence the project goals. Prioritize strategies that are aligned with environmental and organizational values and operational realities.

Environmental Goals

The selection of LEED credits often depends on the project’s environmental context, particularly current energy use and site conditions.

• Energy signature. To understand how the building behaves in response to the outdoor environment, consider its energy signature—an analysis of measured energy use in relation to seasonal fluctuations in temperature. An energy signature highlights seasonal norms that may prompt operating change and alerts the team to operating inefficiencies. In addition, an energy signature provides insight into whether current systems are meeting the building’s heating and cooling needs.
• Energy benchmarks. Compare the building’s energy use against recognized standards. By benchmarking early, the project team will have time to look at monthly trends in energy use intensity and ENERGY STAR score (where appropriate). Staff will become familiar with recording and reading consumption data and be ready to set efficiency goals.
• Site analysis. A detailed site analysis identifies specific conditions—topography, wind patterns, solar availability and shading, water bodies, view corridors—that may guide decisions on rainwater runoff mitigation, landscape water reduction strategies, onsite renewable energy, and other capital investments. Opportunities for improving and preserving the ecological integrity of the site may become clear.

Organizational Goals

Aligning project goals with the owner’s and tenants’ organizational values allows teams to select green operations strategies that make a strong business case. Examine the following.

• Corporate social responsibility report. The owner’s or tenant’s organizational goals and priorities, articulated in this report, may include aspirations that align with LEED credits.
• Organizational annual metrics. Many organizations have requirements for reporting annual statistics on greenhouse gas emissions and waste recycling from their operations. Selecting credits whose achievement improves these metrics will reinforce current efforts.
• Human resources policies. These policies and programs may set goals for health initiatives, employee retention, commute trip reduction, or workplace satisfaction, each of which suggests a focus on credits that target employees’ well-being.
• Shareholders’ or stakeholders’ concerns. Stakeholders in the organization and project development team may have strongly held ideas about specific sustainability issues. Involving them early in the process ensures that their interests are well represented.

The Credit Structure of LEED for Building Operations and Maintenance

For existing buildings pursuing LEED certification, the establishment period is the time when building infrastructure is assessed, policies are drafted, and programs and processes are put in place to enable ongoing performance measurement. The performance period is the continuous implementation of the strategies set during the establishment period.

Each prerequisite and credit lists the establishment and performance requirements separately. The establishment requirements set projects up for compliance with the performance requirements.

Establishment requirements fall into two categories of credits, those based on building components and site infrastructure and those based on policies and plans:

• Building components and site infrastructure are the characteristics and systems of the building.
• Policies and plans are statements that set goals and outline the implementation of operational management strategies.

Performance requirements also typically fall into two categories of credits, those that require discrete actions and those that require ongoing tracking and measurement over time:

• Actions are regularly repeated to inform continued performance and to identify opportunities for improvement.
• Ongoing tracking occurs continually, verifying ongoing high performance and upkeep of building systems.

Understand Performance Periods

LEED for Building Operations and Maintenance certification is based largely on successful outcomes during the performance period, when sustainable operations are being measured.

Many prerequisites and credits require that operating data and other documentation be submitted for the performance period. Since the project’s certification level is based on these outcomes, the performance period may not have any gaps, defined as any period of time longer than one full week.

The initial performance period is the most recent period of operations preceding the certification application. It must be at least three months but no more than 24 months, except as noted in the credit requirements.

All performance periods must overlap and conclude within 30 days of each other. In the example (Table 1), each performance period is at least three months, and the termination dates range from April 1 through April 26.

Table 1. Example performance periods, by credit

* All performance periods must end with the same 30-day interval.
** Minimum duration = 3 months; maximum duration = 24 months

To ensure that certification is awarded based on current building performance data, LEED for Building Operations and Maintenance certification applications must be submitted for review within 60 calendar days of the end of the performance periods. The 60-day period starts the day after the last day of the latest performance period.

In the example given above (Table 1), the last day of a performance period is April 26; the project team must submit its application in 60 days, counting from April 27.

Recertification

Projects must recertify within five years of the previous certification and are eligible as often as every 12 months.

The recertification performance period extends from the date of the previous certification to the date of the recertification application. If projects pursue new credits in the recertification application, they may use the initial certification performance period rules (see Understanding Performance Periods, above), unless otherwise noted in the credit requirements.

Since buildings do not stop operations while waiting for certification, it is recommended that project teams continue to track building performance during the certification review process.

Projects pursuing recertification are required to submit only performance documentation for review; they are not required to submit establishment documentation unless there have been major changes (e.g., major renovations, major addition, management turnover) that prompt review.

LEED Work Plan

It is recommended that LEED applicants follow a series of steps to certification.

Step 1. Select LEED Rating System

The LEED system comprises 21 adaptations designed to accommodate the needs of a variety of market sectors (see Rating System Selection Guidance). For many credits, Further Explanation highlights rating system and project type variations to help teams develop a successful approach.

Step 2. Check minimum program requirements

All projects seeking certification must comply with the minimum program requirements (MPRs) for the applicable rating system, found in this reference guide and on the USGBC website.

Step 3. Define LEED project scope

Review the project’s program and initial findings from the goal-setting workshop to identify the project scope. Considerations include multiple buildings and management variations.

Next, map the LEED project boundary to comply with the minimum program requirements.

Finally, investigate any special certification programs that may apply based on the project’s scope, such as the Volume Program or the Campus Program. If the owner is planning multiple similar projects in different locations, Volume may be a useful program to streamline certification. If the project includes multiple buildings in a single location, Campus may be appropriate.

Step 4. Develop LEED scorecard

Use the project goals to identify the credits and options that should be attempted by the team. The Behind the Intent sections offer insight into what each credit is intended to achieve and may help teams select credits that bring value to the project’s owner, environment, and community.

A gap analysis may identify the feasibility of certain strategies and indicate whether the team should conduct energy audits, commission building systems, or start organizing utility data in preparation for the performance period. Using this information, the team can identify priority and supporting credits.

Finally, establish the target LEED certification level (Certified, Silver, Gold, or Platinum) and identify additional credits needed to achieve it. Make sure that all prerequisites can be met and include a buffer of several points above the minimum in case of changes during the performance period.

Step 5. Assign roles and responsibilities

Select one team member to take primary responsibility for leading the group through the LEED application and documentation process.

Cross-disciplinary team ownership of credit compliance can help foster integrated implementation while ensuring consistent documentation across credits. On a credit- by-credit basis, assign primary and supporting roles to appropriate team members for credit achievement and documentation; this includes assigning responsibility for crucial tasks like water meter reading, purchases tracking, and vendor management. Clarify responsibilities for ensuring that policy and infrastructure upgrade decisions are fully implemented and documented, and that performance outcomes align with operational intent and goals.

Establish regular meeting dates and develop clear communication channels to streamline the process and resolve issues quickly. Double-check that all assignments for surveys, tracking, and audits are clear and that team members understand their roles.

Step 6. Determine performance period

Determining a performance period schedule is necessary for compliance with most credits. All performance periods must end within 30 days of each other and (for a newly attempted credit) last at least three months but no more than 24 months (see Understand Performance Periods, above).

Step 7. Develop consistent documentation

Consistent documentation is critical to LEED certification success. Designate one person as the single point of contact for all LEED documentation. Data accumulated throughout the performance period, such as purchasing activities, should be uploaded regularly to allow the team to track ongoing progress. The Maintaining Consistency in the Application section, below, and the credit category overviews discuss common consistency issues that will affect achievement of multiple credits.

Step 8. Perform quality assurance review and submit for certification

A quality assurance review is an essential part of the work program. A thorough quality control check can improve presentation of the project and avoid errors that require time and expense to correct later in the certification process. The submission should be thoroughly proofread and checked for completeness. In particular, numeric values that appear throughout the submission must be consistent, e.g. site area.

Maintaining Consistency in the Application

Certain issues recur across multiple credits and credit categories and must be treated consistently throughout the submission.

Effective Policy Development

The following components must be included in policies developed for compliance with LEED prerequisites and credits.

Physical and programmatic scope. Describe the physical and programmatic scope of the policy. If any spaces within the building or site are excluded, describe the exemption and explain the reason.

Duration of applicability. Identify the time period to which the policy applies. For example, “This policy shall take effect on XX/XX/XXXX and shall continue indefinitely or until amended and/or replaced by a subsequent sustainable purchasing policy.”

Responsible parties. By full name and title or position, name the person who will implement the policy. If a vendor is responsible for implementing parts of the plan, name both the vendor and the building manager to whom the vendor reports. Including contact information makes it easy for anybody who references the policy to reach the responsible party. If there are multiple responsible parties, consider identifying clearly which components of the policy each oversees.

Sustainability goals and objectives. Identify the sustainability goals of the policy. Goals must be measurable and are typically numerical. For example, “50% of waste (measured by weight) will be diverted from the landfill” or “75% of ice melt purchased will meet sustainability requirements.” Although measurable goals must be set, documentation to demonstrate actual achievement of the set goals is not required for these policies.

Performance evaluation metrics. Explain how actual outcomes and sustainability performance for each element of the policy will be measured and tracked over time. For example, “the percentage of waste diverted will be measured by weight” or “the percentage of cleaning purchases that meet sustainability requirements will be measured by cost.”

Procedures and strategies for implementation. Outline the procedures, strategies, and best management practices to be used to achieve the goals. For projects with multiple tenants, describe how building managers will provide education and guidance to encourage tenants to comply. To help with implementation, list contacts, websites, past experiences, and other resources.

Quality assurance process. Describe how the responsible party will verify that the policy is being implemented, that the metrics reflect the actual outcomes, and that performance persists over time. This may include periodic checks to make sure the policy is consistently implemented and that the set goals are being achieved.

Occupancy

Many kinds of people use a typical LEED building, and the mix varies by project type. Occupants are sometimes referred to in a general sense; for example, “Provide places of respite that are accessible to patients and visitors.” In other instances, occupants must be counted for calculations. Definitions of occupant types are general guidelines that may be modified or superseded in a particular credit when appropriate (such changes are noted in each credit’s reference guide section). Most credits group users into two categories, regular building occupants and visitors.

Regular Building Occupants

Regular building occupants are habitual users of a building. All of the following are considered regular building occupants.

Employees include part-time and full-time employees, and totals are calculated using full-time equivalency (FTE). A typical project can count FTE employees by adding full-time employees and part-time employees, adjusted for their hours of work.

Equation 1. FTE employees = Full-time employees + (Σ daily part-time employee hours) / 8

For buildings with more unusual occupancy patterns, calculate the FTE building occupants based on a standard eight-hour occupancy period.

Equation 2. FTE employees = (Σ all employee hours) / 8

Staff is synonymous with employees for the purpose of LEED calculations.

Volunteers who regularly use a building are synonymous with employees for the purpose of LEED calculations.

Residents of a project are considered regular building occupants. This includes residents of a dormitory. If actual resident count is not known, use a default equal to the number of bedrooms in the dwelling unit plus one, multiplied by the number of such dwelling units.

Primary and secondary school students are typically regular building occupants.

Hotel guests are typically considered regular building occupants, with some credit-specific exceptions. Calculate the number of overnight hotel guests based on the number and size of units in the project. Assume 1.5 occupants per guest room and multiply the resulting total by 60% (average hotel occupancy). Alternatively, the number of hotel guest occupants may be derived from actual or historical occupancy.

Inpatients are medical, surgical, maternity, specialty, and intensive-care unit patients whose length of stay exceeds 23 hours. Peak inpatients are the highest number of inpatients at a given point in a typical 24-hour period.

Visitors

Visitors (also “transients”) intermittently use a LEED building. All of the following are considered visitors:

Retail customers are considered visitors. In Water Efficiency credits, retail customers are considered separately from other kinds of visitors and should not be included in the total average daily visitors.

Outpatients visit a hospital, clinic, or associated health care facility for diagnosis or treatment that lasts 23 hours or less.

Peak outpatients are the highest number of outpatients at a given point in a typical 24-hour period.

Volunteers who periodically use a building (e.g., once per week) are considered visitors.

Higher-education students are considered visitors to most buildings, except when they are residents of a dorm, in which case they are residents.

In calculations, occupant types are typically counted in two ways:

Daily averages take into account all the occupants of a given type for a typical 24-hour day of operation. Peak totals are measured at the moment in a typical 24-hour period when the highest number of a given occupant type is present.

Whenever possible, use actual or predicted occupancies. If occupancy cannot be accurately predicted, one of the following resources to estimate occupancy:

 

 

If numbers vary seasonally, use occupancy numbers that are a representative daily average over the entire operating season of the building.

If occupancy patterns are atypical (shift overlap, significant seasonal variation), explain such patterns when submitting documentation for certification.

Table 2 lists prerequisites and credits that require specific occupancy counts for calculations.

Table 2. Occupancy types for calculations, by project type variation

 

 

Considering Occupant Impact in an Existing Building

Occupants’ interaction with a building may enhance or compromise the sustainability and efficiency goals of the operations team and owner. For example, if the occupants have complete control over temperature and lighting, energy consumption may rise, but too little control may increase complaints to facilities staff. Similarly, an open-office layout that allows views to the outdoors could compromise acoustics and productivity and also affect heating and cooling. Energy efficiency and indoor environmental quality goals entail many such trade-offs.

Making decisions that account for occupant preferences is likely to increase their satisfaction with their working environment and encourage them to take interest in achieving the long term sustainability goals of the organization.

Surveying occupants during the establishment period will shed light on their preferences and needs and help inform project goals at the outset. A subsequent survey will indicate how well the new policies and systems are working.

Tenant Space Exclusion Allowance

Buildings with leased spaces may face particular challenges in earning LEED for Building Operations and Maintenance credits. Whereas the prerequisites address the base building systems or are limited to areas under management control, many credits require commitment and cooperation from tenants. Project teams should review the lease terms and management situation and either obtain commitments from tenants or pursue credits that do not require tenants’ participation. Projects that have a few large tenants may be able to satisfy the requirements more easily than buildings with many small tenant spaces.

Projects may exclude up to 10% of the total gross building floor area from the LEED project boundary, which will apply consistently throughout the submission except in EQ Environmental Tobacco Smoke, where the entire building must be considered. Projects may take an additional 10% exemption on a credit-by-credit basis if it is not possible to gather the necessary tenant data for these credits, or the applicant does not have control over the required element (this additional 10% may not be applied to the EA Prerequisite Minimum Energy Performance). The specific spaces excluded as part of the 10% can vary by credit. Project teams must clearly note which spaces have been excluded in which credit when preparing documentation for certification.

Minimum Occupancy

EA Prerequisite Minimum Energy Performance includes a minimum occupancy requirement. No other credits specify a minimum occupancy threshold.

Variable Occupancy

When occupancy rates vary over the performance period, that variation should be reflected in credit calculations via a time-weighted average.

Generally, for partially occupied buildings, project teams document the performance of the entire building as if it were fully occupied. Because completely vacant or unused space has no activity and may lack the furnishings, fixtures, and equipment intended for regular operations, however, partial occupancy changes the way the performance is documented for the following credits.

WE Prerequisite Indoor Water Use and WE Credit Indoor Water Use

To determine the annual usage of each plumbing fixture type, use the following rules:

 

 

These rules apply to both base building or core fixtures and tenant space fixtures. If fixture upgrades are required to achieve compliance, it is recommended that project teams first focus on base building or core fixtures.

EQ Prerequisite Minimum Indoor Air Quality Performance

For mechanically ventilated spaces that are partially occupied during part the performance period or completely vacant or unused throughout the entire performance period, use the regular procedures, with the following exceptions.

Determine the minimum amount of outdoor air that must be supplied at full occupancy. Perform calculations using the estimated occupancy count if needed.

 

For naturally ventilated spaces, use the normal procedures for this prerequisite.

EQ Credit Enhanced Indoor Air Quality Strategies and EQ Credit Thermal Comfort

For spaces that are completely vacant or unused throughout the entire performance period, the team has two choices:

 

If the space becomes occupied, however, it will need to be included to achieve the credit in future LEED certifications.

Vacant or unused spaces do not need to be monitored or tested during the performance period.

EQ Credit Interior Lighting and EQ Credit Daylight and Views

For spaces that are completely vacant or unused throughout the entire performance period but have furnishings, fixtures, and equipment intended for regular operations, use the regular procedures.

For spaces that are completely vacant or unused throughout the entire performance period, exclude this area from credit calculations and measurements. If a space becomes occupied, however, it will need to be included to achieve the credit in future LEED certifications.

EQ Credit Occupant Comfort Survey

The Occupant Comfort Survey credit requires that survey responses be collected from a representative sample of building occupants, making up at least 30% of the total occupants. For partially occupied buildings, use actual occupancy (or a time-weighted average if occupancy varies through the performance period) to determine how many occupants must be surveyed.

Projects with Several Physically Distinct Structures

Primary and secondary school projects, hospitals (general medical and surgical), hotels, resorts, and resort properties, as defined for ENERGY STAR building rating purposes, are eligible to include more than one physically distinct structure in a single LEED project certification application without having to use the Campus Program, subject to the following conditions.

 

 

Any single structure that is larger than 25,000 square feet (2 320 square meters) must be registered as a separate project or treated as a separate building in a group certification approach.

Quick Reference

Table 3. Credit attributes

 

1. Default occupant density from ASHRAE 62.1-2010, Table 6-1
2. Default occupant density from CEN Standard EN 15251, Table B.2
3. Appendix 2 Default Occupancy Counts
4. Results from applicable studies.
   • For floors or separate tenant spaces that are partially occupied during part of the performance period, use the regular procedures to document prerequisite achievement. Extrapolate partial-year data to derive annual values unless circumstances justify an adjustment.
   • For floors or separate tenant spaces that are completely vacant or unused throughout the entire performance period, base usage on the estimated occupancy count. Allocate occupants to the building’s fixture types in a reasonable way. Create usage groups in the indoor water use reduction calculator to account for the vacant areas.
5. Measure the outdoor airflow rates to determine whether the systems can deliver sufficient ventilation under assumed normal full-occupancy conditions.
6. For actual operation, consider reducing the amount of outdoor air supplied to the partially occupied, vacant, or unused space.
   • Install the appropriate particle filters or air-cleaning devices or monitoring devices, or
   • Exclude the vacant or unused space from the credit requirements.
   • The buildings to be certified must be a part of the same identity. For example, the buildings are all part of the same elementary school, not a mix of elementary school and high school buildings.
   • The project must be analyzed as a whole (i.e., in aggregate) for all minimum program requirements (MPRs), prerequisites, and credits in the LEED rating system.
   • All the land area and all building floor areas within the LEED project boundary must be included in every prerequisite and credit submitted for certification.
   • There is no specific limit on the number of structures, but the aggregate gross floor area included in a single project must not exceed 1 million square feet (92 905 square meters).

GS7_Credit attributes EBOM

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Minimum Program Requirements

The Minimum Program Requirements (MPRs) are the minimum characteristics or conditions that make a project appropriate to pursue LEED certification. These requirements are foundational to all LEED projects and define the types of buildings, spaces, and neighborhoods that the LEED rating system is designed to evaluate. View the Minimum Program Requirements

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Rating System Selection Guidance

Projects are required to use the rating system that is most appropriate. However, when the decision is not clear, it is the responsibility of the project team to make a reasonable decision in selecting a rating system before registering their project. This guidance helps project teams select a LEED rating system. View the Rating System Selection Guidance.

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Credit Category Overviews

• LT Overview
• SS Overview
• WE Overview
• EA Overview
• MR Overview
• EQ Overview
• IN Overview
• RP Overview

LT Overview

The Location and Transportation (LT) category rewards thoughtful project team decisions about the location of tenant space, with credits that encourage compact development, alternative transportation, and connection with amenities, such as restaurants and parks. The LT category is an outgrowth of the Sustainable Sites category, which formerly covered location-related topics. Whereas the SS category now specifically addresses on-site ecosystem services, the LT category considers the existing features of the surrounding community and how this infrastructure affects occupants’ behavior and environmental performance.

Well-located tenant spaces are those that take advantage of existing infrastructure—public transit, street networks, pedestrian paths, bicycle networks, and services and amenities. By recognizing existing patterns of development and land density, project teams can reduce strain on the environment from the social and ecological costs that accompany sprawling development patterns. In addition, the compact communities promoted by the LT credits encourage robust and realistic alternatives to private automobile use, such as walking, biking, vehicle shares, and public transit. These incremental steps can have significant benefits: a 2009 Urban Land Institute study concluded that improvements in land-use patterns and investments in public transportation infrastructure alone could reduce greenhouse gas emissions from transportation in the U.S. by 9% to 15% by 2050¹; globally, the transportation sector is responsible for about one-quarter of energy-related greenhouse gas emissions².

If integrated into the surrounding community, a well-located tenant space can also offer distinct advantages to the owner and users of the space. For owners, locating the tenant space in a vibrant, livable community makes it a destination for residents, employees, customers, and visitors. For occupants, walkable and bikable locations can enhance health by encouraging daily physical activity, and proximity to services and amenities can increase happiness and productivity.

Design strategies that complement and build on the project location are also rewarded in the LT section. For example, by limiting parking, a project can encourage building users to take alternative transportation. By providing bicycle storage, a project can support users seeking transportation options.

Consistent Documentation

Walking and bicycling distances are measurements of how far a pedestrian and bicyclist would travel from a point of origin to a destination, such as the nearest bus stop. This distance, also known as shortest path analysis, replaces the simple straight-line radius used in LEED 2009 and better reflects pedestrians’ and bicyclists’ access to amenities, taking into account safety, convenience, and obstructions to movement. This in turn better predicts the use of these amenities.

Walking distances must be measured along infrastructure that is safe and comfortable for pedestrian: sidewalks, all-weather-surface footpaths, crosswalks, or equivalent pedestrian facilities.

Bicycling distances must be measured along infrastructure that is safe and comfortable for bicyclists: on-street bicycle lanes, off-street bicycle paths or trails, and streets with low target vehicle speed. Project teams may use bicycling distance instead of walking distance to measure the proximity of bicycle storage to a bicycle network in LT Credit Bicycle Facilities. When calculating the walking or bicycling distance, sum the continuous segments of the walking or bicycling route to determine the distance from origin to destination. A straight-line radius from the origin that does not follow pedestrian and bicyclist infrastructure will not be accepted.

Refer to specific credits to select the appropriate origin and destination points. In all cases, the origin must be accessible to all building users, and the walking or bicycling distance must not exceed the distance specified in the credit requirements.

¹U.S. Environmental Protection Agency, Smart Growth and Climate Change, epa.gov/dced/climatechange.htm (accessed September 11, 2012).
²International Council on Clean Transportation, Passenger Vehicles, theicct.org/passenger-vehicles (accessed March 22, 2013).

SS Overview

The Sustainable Sites (SS) category rewards decisions about the environment surrounding the building, with credits that emphasize the vital relationships among buildings, ecosystems, and ecosystem services. It focuses on restoring project site elements, integrating the site with local and regional ecosystems, and preserving the biodiversity that natural systems rely on.

Earth’s systems depend on biologically diverse forests, wetlands, coral reefs, and other ecosystems, which are often referred to as “natural capital” because they provide regenerative services. A United Nations study indicates that of the ecosystem services that have been assessed worldwide, about 60% are currently degraded or used unsustainably¹. The results are deforestation, soil erosion, a drop in water table levels, extinction of species, and rivers that no longer run to the sea. Recent trends like exurban development and sprawl encroach on the remaining natural landscapes and farmlands, fragmenting and replacing them with dispersed hardscapes surrounded by nonnative vegetation. Between 1982 and 2001 in the U.S. alone, about 34 million acres (13 759 hectares) of open space (an area the size of Illinois) was lost to development—approximately 4 acres per minute, or 6,000 acres a day². The rainwater runoff from these hardscape areas frequently overloads the capacity of natural infiltration systems, increasing both the quantity and pollution of site runoff. Rainwater runoff carries such pollutants as oil, sediment, chemicals, and lawn fertilizers directly to streams and rivers, where they contribute to eutrophication and harm aquatic ecosystems and species. A Washington State Department of Ecology study noted that rainwater runoff from roads, parking lots, and other hardscapes carries some 6.3 million gallons of petroleum into the Puget Sound every year—more than half of what was spilled in the 1989 Exxon Valdez accident in Alaska.³

Project teams that comply with the prerequisites and credits in the SS category use low-impact development methods that minimize construction pollution, reduce heat island effects and light pollution, and mimic natural water flow patterns to manage rainwater runoff.

In LEED v4, the SS category combines traditional approaches with several new strategies. These include working with conservation organizations to target financial support for off-site habitat protection (Site Development—Protect or Restore Habitat credit), using low-impact development to handle a percentile storm event (Rainwater Management credit), using three-year aged SRI values for roofs and SR values for nonroof hardscape (Heat Island Reduction credit), and creating a five-year improvement plan for the project site (Site Improvement Plan credit).

¹ UN Environment Programme, State and Trends of the Environment 1987–2001, Section B, Chapter 5, unep.org/geo/geo4/report/05_Biodiversity.pdf.
² U.S. Forest Service, Quick Facts, fs.fed.us/projects/four-threats/facts/open-space.shtml (accessed September 11, 2012).
³ Cornwall, W., Stormwater’s Damage to Puget Sound Huge, Seattle Times (December 1, 2007), seattletimes.com/html/localnews/2004045940_ecology01m.html (accessed on September 14, 2012).

WE Overview

The Water Efficiency (WE) section addresses water holistically, looking at indoor use, outdoor use, specialized uses, and metering. The section is based on an “efficiency first” approach to water conservation. As a result, each prerequisite looks at water efficiency and reductions in potable water use alone. Then, the WE credits additionally recognize the use of nonpotable and alternative sources of water.

The conservation and creative reuse of water are important because only 3% of Earth’s water is fresh water, and of that, slightly over two-thirds is trapped in glaciers¹. Typically, most of a building’s water cycles through the building and then flows off-site as wastewater. In developed nations, potable water often comes from a public water supply system far from the building site, and wastewater leaving the site must be piped to a processing plant, after which it is discharged into a distant water body. This pass-through system reduces streamflow in rivers and depletes fresh water aquifers, causing water tables to drop and wells to go dry. In 60% of European cities with more than 100,000 people, groundwater is being used faster than it can be replenished².

In addition, the energy required to treat water for drinking, transport it to and from a building, and treat it for disposal represents a significant amount of energy use not captured by a building’s utility meter. Research in California shows that roughly 19% of all energy used in this U.S. state is consumed by water treatment and pumping³.

In the U.S., buildings account for 13.6% of potable water use⁴, the third-largest category, behind thermoelectric power and irrigation. Designers and builders can construct green buildings that use significantly less water than conventional construction by incorporating native landscapes that eliminate the need for irrigation, installing water-efficient fixtures, and reusing wastewater for nonpotable water needs. The Green Building Market Impact Report 2009 found that LEED projects were responsible for saving an aggregate 1.2 trillion gallons (4.54 trillion liters) of water⁵. LEED’s WE credits encourage project teams to take advantage of every opportunity to significantly reduce total water use.

Cross-Cutting Issues

The WE category comprises three major components: indoor water (used by fixtures, appliances and processes, such as cooling), irrigation water, and water metering. Several kinds of documentation span these components, depending on the project’s specific water-saving strategies.

Site plans. Plans are used to document the location and size of vegetated areas, and the locations of meters and submeters. Within the building, floorplans show the location of fixtures, appliances, and process water equipment (e.g., cooling towers, evaporative condensers), as well as indoor submeters. The same documentation can be used in credits in the Sustainable Sites category.

Fixture cutsheets. Projects must document their fixtures (and appliances as applicable) using fixture cutsheets or manufacturers’ literature. This documentation is used in the Indoor Water Use Reduction prerequisite and credit.

Alternative water sources. A project that includes graywater reuse, rainwater harvesting, municipally supplied wastewater (purple pipe water), or other reused sources, is eligible to earn credit in WE Credit Outdoor Water Use Reduction, WE Credit Indoor Water Use Reduction, WE Credit Cooling Tower Water Use, and WE Credit Water Metering. But the team cannot apply the same water to multiple credits unless the water source has sufficient water volume to cover the demand of all the uses (e.g., irrigation plus toilet-flushing demand).

Occupancy calculations The Indoor Water Use Reduction prerequisite and credit require projections based on occupant’s usage. The Location and Transportation and Sustainable Sites categories also use project occupancy calculations. Review the occupancy section in Getting Started to understand how occupants are classified and counted. Also see WE Prerequisite Indoor Water Use Reduction for additional guidance specific to the WE section.

Metering and Tracking

The WE credits have significant synergies between installing water meters and documenting savings. Table 1 details the role of water meters in the WE credits.

Table 1. Water metering requirements

¹ U.S. Environmental Protection Agency, Water Trivia Facts, water.epa.gov/learn/kids/drinkingwater/water_trivia_facts.cfm (accessed September 12, 2012).
² Statistics: Graphs & Maps, UN Water, http://www.unwater.org/statistics_use.html (accessed March 8, 2013).
³ energy.ca.gov/2005publications/CEC-700-2005-011/CEC-700-2005-011-SF.PDF
⁴ USGBC, Green Building Facts, http://www.usgbc.org/articles/green-building-facts.
⁵ Green Outlook 2011, Green Trends Driving Growth (McGraw-Hill Construction, 2010), aiacc.org/wp-content/uploads/2011/06/greenoutlook2011.pdf (accessed on September 12, 2012).

EA Overview

The Energy and Atmosphere (EA) category approaches energy from a holistic perspective, addressing energy use reduction, energy-efficient design strategies, and renewable energy sources.

The current worldwide mix of energy resources is weighted heavily toward oil, coal, and natural gas¹. In addition to emitting greenhouse gases, these resources are nonrenewable: their quantities are limited or they cannot be replaced as fast as they are consumed². Though estimates regarding the remaining quantity of these resources vary, it is clear that the current reliance on nonrenewable energy sources is not sustainable and involves increasingly destructive extraction processes, uncertain supplies, escalating market prices, and national security vulnerability. Accounting for approximately 40% of the total energy used today³, buildings are significant contributors to these problems.

Energy efficiency in a green building starts with a focus on design that reduces overall energy needs, such as building orientation and glazing selection, and the choice of climate-appropriate building materials. Strategies such as passive heating and cooling, natural ventilation, and high-efficiency HVAC systems partnered with smart controls further reduce a building’s energy use. Interiors Design and Construction projects can encourage these methods by choosing to locate in buildings that have been designed with efficiency in mind and then continuing the process through actions such as installing efficient lighting and appliances. The generation of renewables on the project site or purchase of green power allows portions of the remaining energy consumption to be met with non–fossil fuel energy, helping to balance the demand on traditional sources.

The commissioning process is critical to ensuring high-performing buildings. Early involvement of a commissioning authority helps prevent long-term maintenance issues and wasted energy by verifying that the design meets the owner’s project requirements and functions as intended. In an operationally effective and efficient building, the staff understands what systems are installed and how they function.

The American Physical Society has found that if current and emerging cost-effective energy efficiency measures are employed in new buildings and in existing buildings as their heating, cooling, lighting, and other equipment is replaced, the growth in energy demand from the building sector could fall from a projected 30% increase to zero between now and 2030⁴. The EA section supports the goal of reduced energy demand through credits related to reducing usage, designing for efficiency, and supplementing the energy supply with renewables.

¹ iea.org/publications/freepublications/publication/kwes.pdf
² cnx.org/content/m16730/latest/
³ unep.org/sbci/pdfs/SBCI-BCCSummary.pdf
sup>4 Energy Future: Think Efficiency (American Physical Society, September 2008), aps.org/energyefficiencyreport/report/energy-bldgs.pdf (accessed September 13, 2012).

MR Overview

The longest part of a building’s life cycle is the use phase, commonly referred to as the operations phase. To target environmental impact reductions during building operations, the Materials and Resources (MR) credit category focuses on the constant flow of products being purchased and discarded to support building operations. The life cycle of these products and materials—from extraction, processing, and transportation to use and disposal—can cause a wide range of environmental and human health harms. To reduce these burdens and thus the overall impact of a building during its operations phase, project teams should take a close look at the purchasing and waste management operations in existing buildings.

Purchasing for Building Maintenance and Renovation

Although renovations to existing buildings generally cause less harm than new construction, the associated materials have already had a significant environmental impact by the time they arrive on site. The extraction or harvesting, manufacture, and transport of these materials contribute to water and air pollution, the degradation of habitats, and the depletion of natural resources. In addition, the introduction of volatile organic compounds (VOCs) and other contaminants to the site can degrade the building’s indoor environmental quality before occupancy begins. Establishing an environmentally preferred purchasing policy for construction materials used for maintenance and renovations not only ensures a consistent approach to material selection but also helps reduce environmental harm by specifying low-VOC, sustainably harvested, or reused materials. Implementing such a policy creates the market demand needed to drive manufacturers to produce materials in a more environmentally preferable way.

Purchasing for Ongoing Operations

In addition to the big expenses incurred during facility maintenance and renovations, buildings also require significant amounts of products, from floor wax to furniture to toilet paper, to ensure smooth operations. Though often overlooked, these ongoing purchases can have a large environmental impact. Like construction materials, the products are associated with environmental burden both before and after they are used in the building. Unlike construction materials, however, these ongoing purchases are often the responsibility of several individuals in different departments, locations, and sometimes companies. An environmental purchasing plan, with procedures, guidelines, and designated responsibilities, is therefore necessary. This MR section addresses both the purchasing and implementation challenges facing existing building projects.

Waste for Building Operations

A significant amount of waste is generated by daily building operations and maintenance activities. Landfill disposal has wide-ranging effects, including soil and groundwater contamination, release of methane and carbon dioxide, and land degradation. Today commercial and institutional buildings typically account for 35% to 45% of total municipal solid waste. The commercial building industry can greatly reduce waste going to landfills and incinerators by targeting two large categories: paper (office paper, paperboard, cardboard) and organics (yard trimmings, food scraps, and wood).

Another important ongoing maintenance waste stream to consider is hazardous waste. One of the most toxic and most common sources of indoor pollution is mercury, which is found in all fluorescent lamps. Standard fluorescent lamps offer high efficiency and long life and are therefore widely used; they light 96% of commercial floor space in the United States. Once removed from a building, they often become part of the municipal solid waste stream and contribute to air, land, and water contamination. Properly storing both new and spent lamps on site and ensuring their safe disposal reduce the environmental damage.

Both building maintenance and renovation inevitably produce construction and demolition waste. The safe storage, installation, and disposal of base building elements, such as carpets, paint, casework, furniture, and lamps, contribute to a healthy environment inside and outside the building. Because renovation and maintenance activities can affect indoor air quality, it is important to comply with safe storage recommendations for materials and follow correct protocols when painting, installing carpets, and working with other base building elements. Reducing contamination during construction and before occupancy can help minimize potential problems, thereby enhancing occupants’ comfort, lowering absenteeism, and improving productivity. Taking time during construction to clean and protect ventilation systems and building spaces can extend the lifetime of ventilation systems and improve their efficiency, reducing energy use.

Cross-Cutting Issues

Required Products and Materials

Each prerequisite and credit outlines the exact scope of the requirements. The prerequisite and credit requirements are divided into two categories: products that are purchased on an ongoing basis, such as lamps, paper goods, or office equipment, and materials purchased for periodic maintenance or renovation work.

Qualifying Products and Exclusions

The MR section related to maintenance and renovation addresses “permanently installed building products,” which as defined by LEED refers to products and materials that create the building or are attached to it. Examples include structure and enclosure elements, installed finishes, framing, interior walls, cabinets and casework, doors, and roof. Most of these materials fall into Construction Specifications Institute (CSI) 2012 MasterFormat Divisions 3-10, 31, and 32. Some products addressed by MR credits fall outside these divisions.

For the Operations and Maintenance rating system, furniture must be included in credit calculations and treated consistently across credits. Also included are items purchased to maintain furniture.

Excluded from MR credits are all mechanical, plumbing, and electrical equipment (MEP), specialty items (e.g., elevators, escalators, process equipment, fire suppression systems), and products purchased for temporary use on the project (e.g., formwork for concrete).

Determining Product Cost

Calculations for purchasing credits are based on product and material cost, which excludes labor required for installation or replacement. Preferably, taxes, shipping, and delivery costs on purchases should be excluded but may be included, provided they are either included or excluded consistently throughout the calculations.

Figure 1. Example material radius

 

 

For this project in western Pennsylvania, the concrete does not meet the location valuation factor requirements: even though the concrete was mixed and purchased within the 100-mile radius, its components—the silica, gravel, Portland cement, and lime—were extracted or made farther away.

For the location valuation factor of salvaged and reused materials, see MR Credit Building Product Disclosure and Optimization—Sourcing of Raw Materials, Further Explanation, Material Reuse Considerations.

Determining Material Contributions of an Assembly

Many sustainability criteria in the MR category apply to the entire product, as is the case for product certifications and programs. However, some criteria apply to only a portion of the product. The portion of the product that contributes to the credit could be either a percentage of a homogeneous material or the percentage of qualifying components that are mechanically or permanently fastened together. In either case, the contributing value is based on weight. Examples of homogeneous materials include composite flooring, ceiling tiles, and rubber wall base. Examples of assemblies (parts mechanically or permanently fastened together) include office chairs, demountable partition walls, premade window assemblies, and doors.

Calculate the value that contributes toward credit compliance as the percentage, by weight, of the material or component that meets the criteria, multiplied by the total product cost (Figure 2, Table 1).

product value ($) = Total product cost ($) x (%) product component by weight x (%) meeting sustainable criteria

Figure 2. Sustainably produced components of $500 office chair

Table 1. Example calculation for $500 office chair

Selecting an Appropriate Purchasing Tracking System

Several credits in the MR section depend on tracking product purchasing decisions and materials types or streams. When deciding on a tracking system, make sure that the strategy works for the project team. A good tracking system is user-friendly, readily accessible, and easily coordinates multiple purchases from a variety of sources. Issues to consider include users’ computer skills and accessibility, language barriers, and the need to merge information from multiple sources.

For example, if many individuals make purchases, an electronic tracking system may make it easier to share or combine purchase data. Standardized tracking tools ease the process of tracking the purchases of different parties and aggregating the data. Keep in mind that some vendors may not have ready access to computers for logging product deliveries.

Steps for using a tracking system proceed as follows:

 

1. Review current purchasing practices to evaluate which items already meet the requirements and what changes need to be made.
2. Log all purchases.
3. Identify which purchases meet the credit criteria.
4. Calculate the percentage, by cost, of portions of materials or assemblies that meet the criteria (in those cases where only a portion of a material meets the criteria).
5. Calculate the total percentage, by cost, of materials that meet the credit criteria.

 

It is recommended that teams pilot the chosen tracking system for one or two months before using it for LEED certification so that any problems can be addressed before the performance period.

Multitenant Buildings

Because certification applies to whole buildings, it may be challenging for multitenant buildings to earn certain credits, especially in the MR category. All portions of a building under the site management’s control are expected to comply with the credit requirements. If it is not possible to gather to necessary information on purchasing or waste management to document credit achievement, or if the LEED applicant does not have control over the entire building, the project team may exempt up to 10% of the building’s gross floor area (see Getting Started).

Collecting waste information in multitenant buildings. Generally, waste collection falls under the responsibility of building management, through a service contract for the entire building. If waste collection or portions of waste collection (e.g., hazardous waste) are not under the site management’s control, it is recommended that teams prioritize meeting local regulations for waste disposal, then focus on prerequisite achievement and, last, credit achievement.

Collecting purchasing information in multitenant buildings. The products, materials, and furniture (as applicable) purchased by tenants are included in the MR purchasing credits. It is recommended that project teams test the building-wide purchasing tracking systems before the start of the performance period. Establish a relationship with the primary purchaser in each tenant space to encourage participation, accurate reporting, and notification when relevant purchases will be made. Provide support (e.g., training in using the tracking tool) and clearly indicate what information is needed.

 

Excluding tenant purchases in credit documentation. If additional tenants beyond those in the excluded 10% gross floor area choose not to provide purchasing data, the purchases for those tenant spaces must be estimated and assumed to be noncompliant. To estimate these tenants’ purchases, extrapolate the purchasing rate from elsewhere in the building on a per occupant or area basis, and assume that the purchases meet none of the criteria. Integrate the estimated data from the nonparticipating tenants into the whole-building purchasing data (for participating and nonparticipating tenants) to determine compliance for the whole building (Table 2).

Table 2. Example compliance calculation with nonparticipating tenants

¹U.S. Environmental Protection Agency, epa.gov/osw/conserve/rrr/imr/cdm/pubs/cd-meas.pdf.
²European Commission Service Contract on Management of Construction and Demolition Waste, Final Report, http://www.eu-smr.eu/cdw/docs/BIO_Construction %20and%20Demolition%20Waste_Final%20report_09022011.pdf (accessed April 9, 2013).
³USGBC, Green Building Facts, USGBC, usgbc.org/ShowFile.aspx?DocumentID=18693 (accessed September 13, 2012).
⁴City of Seattle, LEED Projects Analysis, seattle.gov/dpd/greenbuilding/docs/dpdp022009.pdf (accessed March 26, 2013).
⁵ISO 14040 International Standard, Environmental management, Life cycle assessment, principles and framework (Geneva, Switzerland: International Organization for Standardization, 2006).

EQ Overview

The Indoor Environmental Quality (EQ) category rewards decisions made by project teams about indoor air quality, thermal and visual comfort, and occupants’ satisfaction. Green buildings with good indoor environmental quality protect the health and comfort of building occupants. High-quality indoor environments also enhance productivity, decrease absenteeism, improve the building’s value, and reduce liability for building designers and owners¹.

The relationship between the indoor environment and the health and comfort of building occupants is complex and still not fully understood. Local customs and expectations, occupants’ activities, and the building’s site, design, and construction are just a few of the variables that make it difficult to quantify and measure the direct effect of a building on its occupants². The EQ section encourages project teams to develop policies and programs based on proven methods that prioritize the health and comfort of the building occupants and to measure performance with well-established indicators.

Ventilation has a large effect on the health and well-being of a building’s occupants. Existing buildings’ HVAC systems may have fallen out of calibration or were never designed to provide adequate amounts of outside air for diluting contaminants. The EQ section focuses on optimizing existing HVAC systems and minimizing sources of contaminants, such as cleaning products and laser printers. (Emissions from products used in renovations, maintenance work, and furniture are addressed in the Materials and Resources credit category.) The EQ category also encourages building owners to determine priorities for improving the indoor environment by surveying occupants.

¹ U.S. Environmental Protection Agency, Health Buildings Healthy People: A Vision for the 21st Century, epa.gov/iaq/pubs/hbhp.html (October 2001) (accessed July 25, 2013).
² Mitchell, Clifford S., Junfeng Zhang, Torben Sigsgaard, Matti Jantunen, Palu J. Lioy, Robert Samson, and Meryl H. Karol, Current State of the Science: Health Effects and Indoor Environmental Quality, Environmental Health Perspectives 115(6) (June 2007).

Cross-Cutting Issues

Floor Area Calculations and Floor Plans

For many of the credits in the EQ category, compliance is based on the percentage of floor area that meets the credit requirements. In general, floor areas and space categorization should be consistent across EQ credits. Any excluded spaces or discrepancies in floor area values should be explained and highlighted in the documentation. See Space Categorization, below, for additional information on which floor area should be included in which credits.

Space Categorization

The EQ category focuses on the interaction between the occupants of the building and the indoor spaces in which they spend their time. For this reason, it is important to identify which spaces are used by the occupants, including any visitors (transients), and what activities they perform in each space. Depending on the space categorization, the credit requirements may or may not apply (Table 1).

Occupied versus unoccupied space

All spaces in a building must be categorized as either occupied or unoccupied. Occupied spaces are enclosed areas intended for human activities. Unoccupied spaces are places intended primarily for other purposes; they are occupied only occasionally and for short periods of time—in other words, they are inactive areas.

Examples of spaces that are typically unoccupied include the following:

 

• Mechanical and electrical rooms
• Egress stairway or dedicated emergency exit corridor
• Closets in a residence (but a walk-in closet is occupied)
• Data center floor area, including a raised floor area
• Inactive storage area in a warehouse or distribution center

 

For areas with equipment retrieval, the space is unoccupied only if the retrieval is occasional.

Regularly versus nonregularly occupied spaces

Occupied spaces are further classified as regularly occupied or nonregularly occupied, based on the duration of the occupancy. Regularly occupied spaces are enclosed areas where people normally spend time, defined as more than one hour of continuous occupancy per person per day, on average; the occupants may be seated or standing as they work, study, or perform other activities. For spaces that are not used daily, the classification should be based on the time a typical occupant spends in the space when it is in use. For example, a computer workstation may be largely vacant throughout the month, but when it is occupied, a worker spends one to five hours there. It would then be considered regularly occupied because that length of time is sufficient to affect the person’s well-being, and he or she would have an expectation of thermal comfort and control over the environment.

Occupied spaces that do not meet the definition of regularly occupied are nonregularly occupied; these are areas that people pass through or areas used an average of less than one hour per person per day.

Examples of regularly occupied spaces include the following:

Airplane hangar	Hospital operating room	Private office
Auditorium	Hospital patient room	Reception desk
Auto service bay	Hospital recovery area	Residential bedroom
Bank teller station	Hospital staff room	Residential dining room
Conference room	Hospital surgical suite	Residential kitchen
Correctional facility cell or day room	Hospital waiting room	Residential living room
Data center network operations center	Hospital diagnostic and treatment area	Residential office, den, workroom
Data center security operations center	Hospital laboratory	Retail merchandise area and associated circulation
Dorm room	Hospital nursing station	Retail sales transaction area
Exhibition hall	Hospital solarium	School classroom
Facilities staff office	Hospital waiting room	School media center
Facilities staff workstation	Hotel front desk	School student activity room
Food service facility dining area	Hotel guest room	School study hall
Food service facility kitchen area	Hotel housekeeping area	Shipping and receiving office
Gymnasium	Hotel lobby	Study carrel
Hospital autopsy and morgue	Information desk	Warehouse materials-handling area
Hospital critical-care area	Meeting room
Hospital dialysis and infusion area	Natatorium
Hospital exam room	Open-office workstation

Examples of nonregularly occupied spaces include the following:

Break room
Circulation space
Copy room
Corridor
Fire station apparatus bay
Hospital linen area
Hospital medical record area
Hospital patient room bathroom
Hospital short-term charting space
Hospital prep and cleanup area in surgical suite
Interrogation room
Lobby (except hotel lobby)*
Locker room
Residential bathroom
Residential laundry area
Residential walk-in closet
Restroom
Retail fitting area
Retail stock room
Shooting range
Stairway

*Hotel lobbies are considered regularly occupied because people often congregate, work on laptops, and spend more time there than they do in an office building lobby.

Occupied space subcategories

Occupied spaces, or portions of an occupied space, are further categorized as individual or shared multioccupant, based on the number of occupants and their activities. An individual occupant space is an area where someone performs distinct tasks. A shared multioccupant space is a place of congregation or a place where people pursue overlapping or collaborative tasks. Occupied spaces that are not regularly occupied or not used for distinct or collaborative tasks are neither individual occupant nor shared multioccupant spaces.

Examples of individual occupant spaces include the following:

Bank teller station
Correctional facility cell or day room
Data center staff workstation
Hospital nursing station
Hospital patient room
Hotel guest room
Medical office
Military barracks with personal workspaces
Open-office workstation
Private office
Reception desk
Residential bedroom
Study carrel

Examples of shared multioccupant spaces include the following:

Active warehouse and storage
Airplane hangar
Auditorium
Auto service bay
Conference room
Correctional facility cell or day room
Data center network operations center
Data center security operations center
Exhibition hall
Facilities staff office
Food service facility dining area
Food service facility kitchen area
Gymnasium
Hospital autopsy and morgue
Hospital critical-care area
Hospital dialysis and infusion area
Hospital exam room
Hospital operating room
Hospital surgical suite
Hospital waiting room
Hospital diagnostic and treatment area
Hospital laboratory
Hospital solarium
Hotel front desk
Hotel housekeeping area
Hotel lobby
Meeting room
Natatorium
Retail merchandise area and associated circulation
Retail sales transaction area
School classroom
School media center
School student activity room
School study hall
Shipping and receiving office
Warehouse materials-handling area

Occupied spaces can also be classified as densely or nondensely occupied, based on the concentration of occupants in the space. A densely occupied space has a design occupant density of 25 people or more per 1,000 square feet (93 square meters), or 40 square feet (3.7 square meters) or less per person. Occupied spaces with a lower density are nondensely occupied.

Table 1 outlines the relationship between the EQ credits and the space categorization terms. If the credit is listed, the space must meet the requirements of the credit.

Table 1. Space types in EQ credits

Table 2 outlines the relationship between the EQ credits and the space categorization terms specific to each rating system (see Definitions). Unless otherwise stated, if the credit is listed, the space must meet the requirements of the credit.

Table 2. Rating system–specific space classifications

*Hotel guest rooms are excluded from the credit requirements.

The following credits are not affected by space classifications:

• Environmental Tobacco Smoke Control
• Green Cleaning Policy
• Indoor Air Quality Management Program
• Enhanced Indoor Air Quality Strategies, Option 1
• Enhanced Indoor Air Quality Strategies, Option 2, Outdoor Air Monitoring for Mechanically Ventilated Spaces
• Enhanced Indoor Air Quality Strategies, Option 2 Outdoor Air Monitoring for Naturally Ventilated Spaces
• Enhanced Indoor Air Quality Strategies, Option 2, Alarmed Openings for Naturally Ventilated Spaces
• Interior Lighting, Option 2, strategy B
• Interior Lighting, Option 2, strategy C
• Interior Lighting, Option 2, strategy F
• Green Cleaning—Custodial Effectiveness Assessment
• Green Cleaning—Products and Materials
• Green Cleaning—Equipment
• Integrated Pest Management
• Occupant Comfort Survey

Tricky Spaces

Pay extra attention to how the following types of spaces are classified in specific credits.

Residential

• Minimum Indoor Air Quality Performance and Environmental Tobacco Smoke have specific requirements and considerations for residential projects.
• See the Project Type Variations sections in Interior Lighting for guidance on providing appropriate controllability in residential buildings.

Auditoriums

• Exceptions to Daylight and Quality Views are permitted. See the Project Type Variations sections in Daylight and Quality Views.

Gymnasiums

• See the Project Type Variations section in Thermal Comfort for guidance on dealing with high levels of physical activity.
• An exception to the views requirements in Daylight and Quality Views is permitted. See the Project Type Variations section in Daylight and Quality Views.

Transportation Terminals

• For Interior Lighting, Option 1, Lighting Control, most of the areas in a transportation terminal can be considered shared multioccupant. Most areas in transportation terminals are also regularly occupied.

Dormitories and Military Barracks

• These spaces fall in-between a work space and residence.
• Dorm rooms or military barracks with personal workspaces are considered individual occupant spaces. Military barracks without personal workspaces are considered shared multioccupant.

Industrial Facilities

• For Interior Lighting, Option 1, Lighting Control, most of the active warehouse and storage areas are considered multioccupant.
• Most areas in industrial facilities are also regularly occupied.

IN Overview

Sustainable design strategies and measures are constantly evolving and improving. New technologies are continually introduced to the marketplace, and up-to-date scientific research influences building design strategies. The purpose of this LEED category is to recognize projects for innovative building features and sustainable building practices and strategies.

Occasionally, a strategy results in building performance that greatly exceeds what is required in an existing LEED credit. Other strategies may not be addressed by any LEED prerequisite or credit but warrant consideration for their sustainability benefits. In addition, LEED is most effectively implemented as part of a cohesive team, and this category addresses the role of a LEED Accredited Professional in facilitating that process.

RP Overview

Because some environmental issues are particular to a locale, volunteers from USGBC chapters and the LEED International Roundtable have identified distinct environmental priorities within their areas and the credits that address those issues. These Regional Priority credits encourage project teams to focus on their local environmental priorities.

USGBC established a process that identified six RP credits for every location and every rating system within chapter or country boundaries. Participants were asked to determine which environmental issues were most salient in their chapter area or country. The issues could be naturally occurring (e.g., water shortages) or man-made (e.g., polluted watersheds) and could reflect environmental concerns (e.g., water shortages) or environmental assets (e.g., abundant sunlight). The areas, or zones, were defined by a combination of priority issues—for example, an urban area with an impaired watershed versus an urban area with an intact watershed.

The participants then prioritized credits to address the important issues of given locations. Because each LEED project type (e.g., a data center) may be associated with different environmental impacts, each rating system has its own RP credits.

The ultimate goal of RP credits is to enhance the ability of LEED project teams to address critical environmental issues across the country and around the world.

¹ U.S. Environmental Protection Agency, Health Buildings Healthy People: A Vision for the 21st Century, epa.gov/iaq/pubs/hbhp.html (October 2001) (accessed July 25, 2013).
² Mitchell, Clifford S., Junfeng Zhang, Torben Sigsgaard, Matti Jantunen, Palu J. Lioy, Robert Samson, and Meryl H. Karol, Current State of the Science: Health Effects and Indoor Environmental Quality, Environmental Health Perspectives 115(6) (June 2007).