DRAFT Sampling Protocol

For the LEED for Homes Program

Applicable to multi-familybuildings

(Balloted Version)

This document provides guidance on using the Sampling Protocol to verifyLEED Homes in multifamily buildings. It includes information explaining in what cases and for which LEED for Homes credits sampling is appropriate, as well the procedures that builders, Raters, and LEED for Homes Providers must follow when using sampling.

This sampling protocol only applies to buildings that contain six or more separate dwelling units (hereafter referred to as ‘units’). Buildings with fewer units than this may not conduct sampling.

Note that sampling is not a shortcut to LEED for Homes Certification. This sampling protocol is intended to be a sharing of quality assurance tasks between the builder and Rater. As a builder assumes more responsibility for quality assurance, less need exists for the Rater’s involvement in the QA of the LEED Homes. The sampling rate allowed is proportional to the relative roles of the builder and the Rater.

Raters are encouraged to only use sampling rates that are appropriate for the level of green home building skills demonstrated by each builder, and to ensure that the use of sampling does not reduce the quality of any certified LEED Home.

Sampling refers to verification and testing, not implementation. Each and every home must be built to the same high LEED for Homes standard, and include all of the measures appropriate to meet the goals of the builder / subdivision.

Glossary of Terms

Tested Homes– the units in the multifamily building that are selected for testing and verification.

LEED Requirements for Sampling – the list of LEED for Homes measures that areincorporated into all of the units in the multi-family building. Unlike production homes that can separated into multiple sample sets, multi-family building units must all meet the same performance tier and include the same measures.

US GreenBuilding CouncilPage 1February 13, 2008

DRAFT – DO NOT DISTRIBUTE

LEED for Homes Sampling Protocol for multi-family buildings

Failed Item[1]– any credit contained in the LEED Requirements for Sampling that is not met in a Tested Home, including insulation installation, duct leakage, prescriptive air sealing requirements, room-by-room air flows, mechanical system efficiency, irrigation efficiency, lot permeability, etc.

Eligibility

To ensure that all the units in a multi-family building meet the high standard of the LEED for Homes program, theLEED for Homes Provider, the Rater, and the Builder must meet minimum qualifications before using the LEED for Homes Sampling Protocol.

LEED for Homes Provider Qualifications

All LEED for Homes Providers that choose to use this sampling protocol must be approved by USGBC to do so. This approval is granted on a case-by-case basis, but requires the submittal of the following information to USGBC:

  • The name of the Provider’s “sampling manager” (e.g., LEED for Homes Certifier), or the person who oversees all sampling, ensures that it is done properly, and trains the Raters.
  • The list of Raters that will be eligible to rate sampled multi-family buildings.
  • A list of other relevant qualifications, including:
  • An estimate of the number of homes that the LEED for Homes Provider has individually qualified as:
  • ENERGY STAR labeled homes
  • LEED Homes
  • A list of any ENERGY STAR projects that the LEED for Homes Provider has completed involved sampling, including the status of the projects and the number of homes;
  • A list of the LEED for Homes Provider’sexperience in training subcontractors on a wide range of green home building measures.
  • A list of other related experience, including: research work, provider field technician, etc.

Rater Qualifications

The LEED for Homes Provider will submit the following information to USGBC:

  • An estimate of the number of homes that the Rater has individually qualified as:
  • ENERGY STAR labeled homes
  • LEED Homes
  • A list of any ENERGY STAR projects that the Rater has completed involving sampling, including the status of the projects and the number of homes / units.

Builder Qualifications

All builders must meet the following requirements to qualify to use the Sampling Protocol for LEED Homes.

  • Builder must submit a completed and signed LEED for Homes Builder Agreement.
  • Builder must have established procedures for training subcontractors and incorporating in-house quality control techniques (See Step 1 below).
  • Builder must identify an on-site liaison (e.g. construction supervisor) that can work with the Provider or Rater during inspections and respond to potential failures.
  • Builder must have the consent of the LEED for Homes Provider that sampling is acceptable and appropriate, based on the builder’s quality management process, prior experience with green building practices, and/or prior experience with sampling.

Applicability

The LEED for Homes Sampling Protocol is only applicable to certain types of projects. Please check that each project meets the following criteria before initiating sampling:

  • The entire multi-family building shall be of the same construction type using the same envelope systems.
  • All units in the building must have a core set of common LEED for Homes measures, hereafter called the LEED Requirementsfor Sampling.

The LEED Requirements for Sampling

The Sampling Protocol is designed to reduce verification costs for multi-family buildings. Please note that the certification fees paid to USGBC are not reduced as a result of using this Sampling Protocol. In order to use this Protocol, the building must have one list of LEED for Homes measures that are common to all of the units. This list is referred to here as the LEED Requirements for Sampling.

If some units contain additional LEED measures, the Rater may either:

  • Rateeach unit separately (i.e. don’t use sampling), or
  • Rate the units as if they were the same as the others in thebuilding (i.e., without credit for the additional LEED measures).

Even if each unit is rated separately, all of the units in the building must have the same Performance Tier. This Performance Tier must be equal to the lowest Performance Tier achieved by any unit in the building.

Relationship between Quality Management and Sampling Protocol

Many builders have existing and well-developed quality management plans. Other builders do not have one. Sampling is a process whereby the responsibility for quality management is shared between the builder and the Rater. The builder’s quality management plan is the builder’s commitment to their share of the quality management process. This sampling protocol is the Raters commitment to their share of the quality management process - which is highly dependent on the builder’s ability and commitment.

A builder that chooses to use this sampling protocol should have a quality management plan. If the builder does not have one, the first step is to create one. Basic elements of a quality management plan include:

  1. Designate and train builder’s in-field supervisors and their specific oversight and sign-off responsibilities;
  2. Develop detailed scopes of work for each tradethat are focused on quality-critical tasks;
  3. Include scopes of work, and compliance requirements in all trade contracts;
  4. Plan and conduct kick-off meetings for each project (e.g., multifamily building or buildings) where performance goals and consequences of missing performance goals are clearly specified;
  5. Provide appropriate training on green home building, inspections, and performance testing requirements to all trades before starting work on the project;
  6. Require trade and builder supervisor approval and sign-off on all quality-critical measures; and
  1. Schedule the Rater to be on-site during the completion of each measure (that requires testing) in the first four units in the building.

Step 1: Preparation and planning

  1. Builder conducts a preliminary meeting (in person or by phone) with the “sampling manager” to discuss and learn the terms and implications of sampling. This meeting should happen well in advance of the first inspections. Ideally, this discussion should happen at the time of signing the builder agreement (i.e., pre-design and pre-construction).
  2. Builder assembles an integrated project team, including the capabilities described in ID 1.2. Builder defines the roles and responsibilities for each member of the Project Team within the context of sampling and on-site quality control.
  3. Builder and the appropriate members of the project team meet with Provider to conduct a preliminary rating, as per ID credit 1.1. The Rater may make general recommendations on additional measures that builder may need to consider. The builder team and the Rater will agree on the LEED Requirements for Sampling – the suite of credits that have been selected to meet the target performance tier.
  4. If the builder plans to use the performance pathway in the EA category, the Rater must conduct a preliminary “worst-case” energy rating. This energy rating must be conducted for the “worst-case” units in the building (based on position in the building, orientation, window glazing, etc.). The worst-case unit in multi-family buildings is not obvious, and the Rateris encouraged to rate several different units to identify the worst-case energy rating.
  5. The builder will meet with the entire project team, either individually, at a project team meeting, or through a design charrette (as in ID credit 1.3), to explain the measures that are applicable to each trade or sub-contractor.
  6. The builder is encouraged to host in-house training sessions with anyone involved in construction, including trades and sub-contractors, to ensure that all design decisions are implemented consistently and properly in the field.

Step 2: Initial Testing and Verification

In order to qualify for sampling, a multi-family building must have testing and verificationcompleted on at leastfiveconsecutive units without any failures.

The initial testing and verification phase is particularly important in multi-family buildings because this is the best opportunity for the Rater to identify problem areas and communicate them to the construction crew before the rest of the building is completed. For this reason, the on-site liaison (e.g. construction supervisor) must be present during the initial testing and verification phase.

When selecting the initial sampling set, the Rater should try to select different models or units with different layouts. If possible, the initial testing should include at least one of the units that was previously identified as having the worst-case energy rating.

If any failures occur, the Rater should work with the on-site liaison to identify the source of the failure, remedy the problem, and communicate the source of the problem (and its resolution) to all relevant construction crew.

If any failures occur, the building must continue to undergo testing and verification on all units until fiveunits are consecutively verified without any failures.

If a LEED for Homes Provider lacks confidence in a builder’s ability to show consistency in green building techniques, or if a builder is new to green homebuilding, the Provider is entitled to extend this initial testing and verification phase.

Step3: Inspecting Units

Tested Sets

Unlike production homes, multi-family buildings do not have separate and distinct sample sets. All of the units in a multi-family building are treated as part of the same sample set, must have the same LEED Requirements for Sampling, and the same performance tier.

The builder must identifya set of units that are simultaneously ready for diagnostics. Each unit should have drywall complete, interior door jams installed, HVAC system installed, and final air sealing completed. The Rater must be able to choose the Tested Set randomly and without preference or bias.

When selecting the Tested Set, the Rater should select different models to ensure an effective sample. The Tested Set should always include at least one of the units that was previously identified as having the worst-case energy rating.

Sample Testing and Verification

The Rater randomly chooses a sub-set of the units(per Exhibit 1), and then conducts the appropriate testing and verification for those homes.

Exhibit 1

Recommended Sampling Rates for Multi-family Buildings

in the LEED for Homes Program

Type of Builder / Project / Description of Green Home-Building Experience and Initial Performance Test Results / Sampling Rate
Tier 1 / Has built several green buildings and has a strong in-house quality management program. Experienced no problems during the initial testing phase. / 10% (1 out of 10)
Tier 2 / Has built at least one or two green buildings and has an in-house quality management program. Experienced very few complications during the initial testing phase / 15% (1 out of 7)
Tier 3 / Has never built a green home and/or experienced some complications during the initial testing phase / 20% (1 out of 5)

Step4: Responding to Failures

Initial Failures

If any rated unit experiences a Failed Item (i.e. any measure does not meet specified level determined in the LEED Requirements for Sampling), the following must occur immediately:

  1. The builder fixes the cause(s) of failure in all units in the Sample Set.
  2. The builder and Rater must undertake a root-cause analysis to identify the source of the problem causing the failure. This can be done on-site.
  3. The builder communicates the results of the root-cause analysis to all members of the team, and conducts necessary training for all relevant team members on-site, including trades and sub-contractors.
  4. For the remaining units, the Failed Item should be inspected and tested at the sampling rate of the lower Tier. If the project is already Tier 3, begin testing for the Failed Item in 1 out of every 3 units.
  5. The builder demonstrates to the Rater’s satisfaction that any and all sources of failure have been remedied, and the builder is ready to consistently comply with the LEED for Homes Rating System.

Additional Failures

If there is a failure in an already-identified Failed Item, the following occurs:

  1. The builder fixesthe Failed Item in all units in the Sample Set.
  2. The builder and Rater must undertake a root-cause analysis to identify the source of the problem causing the failure.This can be done on-site.
  3. The builder communicates the results of the root-cause analysis to all members of the team, and conducts necessary training for all relevant team members on-site, including trades and sub-contractors.
  4. All units in previous sample sets must be individually inspected and tested for LEED for Homes compliance regarding the Failed Item.
  5. The project is downgraded to a lower tier, and the remaining units will be inspected and tested at a higher rate for all measures, not just the Failed Item. If the project is already Tier 3, begin testing 1 out of every 3 units.

Step 5: Provider Reports Certified Homes

If each tested unit is successfully inspected and verified and all measures in the LEED Requirements for Sampling are met or exceeded, then the building is ready to be certified. Each unit will receive the same LEED score and will be certified at the same Performance Tier.

No unit may be certified as a LEED Home separately from the rest of the building.

The LEED for Homes Provider must keep a record of every unit in the building, both tested and not, and of any failures and their resolution.

How to Verify Different LEED for Homes Credits

Each building will include measures from each of fourdifferent categories:

  • Non-sampled measures
  • Building-wide measures
  • Measures with performance thresholds
  • Prescriptive measures

Each of these categories requires a different approach to inspection and verification.

Non-Sampled Measures

Some measures in the rating system must be verified for each unit in the multi-family building. Where applicable, units with identical designs can duplicate verification to the Rater. These measures include:

  • EQ 4.1 – The builder must demonstrate that each unit complies with the basic outdoor air ventilation requirements in this prerequisite. One Accountability Form can be signed for all of the entire building, but the HVAC contractor must conduct appropriate calculations and designs for each unit.
  • EQ 6.1 – The builder must ensure that room-by-room load calculations are performed separately for each unit, as per the requirements in the measure. One Accountability Form can be signed for the entire building, but the HVAC contractor must conduct appropriate calculations and designs for each unit separately.

Building-wide Measures