Quiz LEED-AP-Homes: US Green Building Council LEED AP Homes (Residential)

The LEED for Homes Rating System (v4) outlines the requirements for the Location and
Transportation (LT) Credit: Site Selection, which includes Option 2: Infill Development. This credit
encourages development on sites that minimize environmental impact by utilizing previously
disturbed or developed land. For a site to qualify as infill development, a specific portion of its
perimeter must border land that has been previously disturbed.
According to the LEED Reference Guide for Homes Design and Construction (v4), the requirement for
Option 2: Infill Development is as follows:
Option 2. Infill Development (1 point)
Select a lot such that at least 75% of the perimeter of the project site immediately borders parcels
that are previously developed or that have been graded or otherwise altered by direct human
activities.
Source: LEED Reference Guide for Homes Design and Construction, v4, Location and Transportation
Credit: Site Selection, p. 54.
This means that 75% of the site’s perimeter must border previously disturbed land to meet the infill
development criteria. The population of the town (10,000 in this case) does not directly affect the
infill development requirement but may be relevant for other LT credits, such as Access to Quality
Transit or Neighborhood Pattern and Design, which consider community size or density. However, for
Site Selection, Option 2, the focus is solely on the perimeter bordering previously disturbed land.
The LEED v4.1 for Homes rating system aligns with this requirement, as it maintains the same infill
development criteria for residential projects under the LT category:
LT Credit: Site Selection, Option 2. Infill Development
At least 75% of the project site’s perimeter must border previously developed or disturbed parcels.
Source: LEED v4.1 Residential BD+C, Credit Library, accessed via USGBC LEED Online.
The LEED AP Homes Candidate Handbook confirms that the exam tests knowledge of the LEED v4
rating system, including the LT credits, and references the LEED Reference Guide for Homes Design
and Construction as a primary study resource. The handbook does not alter the technical
requirements but emphasizes understanding credit intent and compliance paths, such as the infill
development perimeter rule.
Why not the other options?
A . 25%: This is too low and does not meet the minimum threshold for infill development, which
requires significant adjacency to previously disturbed land to ensure compact, sustainable
development.
B . 50%: While closer, 50% still falls short of the 75% requirement, which is designed to prioritize sites
fully integrated into existing developed areas.
D . 100%: Requiring 100% of the perimeter to border previously disturbed land is overly restrictive
and not specified in the LEED v4 or v4.1 requirements.
References:
LEED Reference Guide for Homes Design and Construction, v4, USGBC, Location and Transportation
Credit: Site Selection, p. 54.
LEED v4.1 Residential BD+C, USGBC LEED Credit Library, accessed via LEED Online
(https://www.usgbc.org/credits).
LEED AP Homes Candidate Handbook, GBCI, October 2024, p. 12 (references study resources and
exam scope based on LEED v4).
USGBC LEED for Homes Rating System (v4), available via USGBC website
(https://www.usgbc.org/resources/leed-homes-design-and-construction-v4).
LEED v4.1 for Homes, USGBC, accessed via LEED Online, confirming alignment with v4 infill
requirements.

Minimizing envelope leakage is a critical component of improving energy efficiency in homes, as it
reduces unintended air infiltration and exfiltration through the building envelope. This concept is
addressed in the LEED for Homes Rating System (v4) under the Energy and Atmosphere (EA)
category, specifically in credits related to Air Infiltration and Building Envelope Performance.
According to the LEED Reference Guide for Homes Design and Construction (v4), the primary method
to minimize envelope leakage is to install a continuous air barrier:
EA Prerequisite: Minimum Energy Performance
To reduce air infiltration, projects must include a continuous air barrier system that is sealed at all
penetrations, joints, and interfaces to prevent air leakage. The air barrier must be installed around
the entire building envelope, including walls, roofs, and floors.
Source: LEED Reference Guide for Homes Design and Construction, v4, Energy and Atmosphere
Prerequisite: Minimum Energy Performance, p. 112.
Additionally, the LEED v4.1 Residential BD+C rating system reinforces this requirement:
EA Credit: Air Infiltration
Install a continuous air barrier system to control air leakage through the building envelope. The air
barrier must be airtight, durable, and continuous, with all seams, penetrations, and transitions
sealed.
Source: LEED v4.1 Residential BD+C, Credit Library, accessed via USGBC LEED Online.
A continuous air barrier is a system of materials (e.g., house wraps, sealed drywall, or spray foam)
that forms a complete barrier to air movement, significantly reducing energy losses due to leakage.
This is a proactive design and construction strategy to achieve energy efficiency goals.
Why not the other options?
A . Installing a drainage plane: A drainage plane (e.g., house wrap or rainscreen) is designed to
manage water infiltration and protect the building from moisture damage, not to control air leakage.
While it may contribute to overall building durability, it does not address envelope air tightness.
Reference: LEED Reference Guide for Homes Design and Construction, v4, Sustainable Sites Credit:
Rainwater Management, p. 76, which discusses drainage planes in the context of moisture control.
B . Conducting a blower door test: A blower door test is a diagnostic tool used to measure air leakage
in a building, not to minimize it. It quantifies the air tightness of the envelope (in air changes per
hour, ACH) but does not physically reduce leakage. It is required for verification in LEED v4 (EA Credit:
Air Infiltration) but is not a solution for minimizing leakage.
Reference: LEED Reference Guide for Homes Design and Construction, v4, EA Credit: Air Infiltration,
p. 124.
D . Specifying HERS Grade II Insulation: HERS (Home Energy Rating System) insulation grades refer to
the quality of insulation installation, with Grade II indicating moderate defects. While proper
insulation reduces conductive heat loss, it does not directly address air leakage, which is managed by
the air barrier system.
Reference: LEED Reference Guide for Homes Design and Construction, v4, EA Credit: Insulation, p.
120, which discusses HERS insulation grades but not air leakage.
The LEED AP Homes Candidate Handbook emphasizes the importance of understanding EA credits,
including air infiltration, for the exam, referencing the LEED Reference Guide for Homes Design and
Construction as a key study resource. The handbook confirms that the exam is based on LEED v4,
ensuring the relevance of the continuous air barrier requirement.
References:
LEED Reference Guide for Homes Design and Construction, v4, USGBC, Energy and Atmosphere
Prerequisite: Minimum Energy Performance, p. 112, and EA Credit: Air Infiltration, p. 124.
LEED v4.1 Residential BD+C, USGBC LEED Credit Library, accessed via LEED Online
(https://www.usgbc.org/credits).
LEED AP Homes Candidate Handbook, GBCI, October 2024, p. 12 (references study resources and
exam scope based on LEED v4).
USGBC LEED for Homes Rating System (v4), available via USGBC website
(https://www.usgbc.org/resources/leed-homes-design-and-construction-v4).
LEED v4.1 for Homes, USGBC, accessed via LEED Online, confirming air barrier requirements.

Duct leakage in HVAC systems can significantly increase energy losses, particularly when ducts are
poorly sealed or located in areas that exacerbate the impact of leakage. This issue is addressed in the
LEED for Homes Rating System (v4) under the Energy and Atmosphere (EA) category, specifically in
credits related to Heating and Cooling Distribution Systems.
According to the LEED Reference Guide for Homes Design and Construction (v4), the location of ducts
plays a critical role in energy losses due to leakage:
EA Credit: Heating and Cooling Distribution Systems
To minimize energy losses, locate all heating and cooling ducts and air handlers within the
conditioned envelope of the building. Ducts located in unconditioned spaces, such as attics,
basements, or exterior walls, are more likely to lose energy due to leakage, as air escaping from
ducts in these areas is lost to the outside or unconditioned zones, increasing heating and cooling
loads.
Source: LEED Reference Guide for Homes Design and Construction, v4, Energy and Atmosphere
Credit: Heating and Cooling Distribution Systems, p. 126.
The LEED v4.1 Residential BD+C rating system further clarifies this:
EA Credit: Optimize Energy Performance
Ducts located in unconditioned spaces (e.g., attics, unconditioned basements, or exterior walls)
contribute to significant energy losses when leakage occurs, as conditioned air escapes to areas
outside the thermal envelope. Sealing ducts and locating them within conditioned spaces are best
practices to minimize losses.
Source: LEED v4.1 Residential BD+C, Credit Library, accessed via USGBC LEED Online.
Ducts in unconditioned attics, basements, or exterior walls are particularly problematic because any
leakage results in conditioned air being lost to spaces that are not temperature-controlled, requiring
the HVAC system to work harder to maintain indoor comfort. This scenario maximizes energy losses
compared to ducts within the conditioned envelope.
Why not the other options?
A . Interior wall cavities are used to conduct return air: Using interior wall cavities for return air is not
a best practice and may cause pressure imbalances or air quality issues, but it is less likely to cause
significant energy losses due to supply duct leakage. Return air systems are typically within
conditioned spaces, and the primary concern is airflow efficiency, not energy loss to unconditioned
areas.
Reference: LEED Reference Guide for Homes Design and Construction, v4, EA Credit: Heating and
Cooling Distribution Systems, p. 127, which discusses return air strategies but not as a primary
leakage concern.
B . Duct layout includes multiple 90-degree bends on a single branch: Multiple 90-degree bends
increase airflow resistance, reducing system efficiency, but they do not directly cause duct leakage.
Leakage is related to unsealed joints or poor duct construction, not the geometry of the duct layout.
Reference: LEED Reference Guide for Homes Design and Construction, v4, EA Credit: Heating and
Cooling Distribution Systems, p. 126, which prioritizes duct sealing over layout.
C . Ducts are located within conditioned envelope but joints are unsealed: While unsealed joints
cause leakage, ducts within the conditioned envelope leak into spaces that are already temperature-
controlled. This reduces the energy impact compared to leakage in unconditioned spaces, as the
conditioned air remains within the thermal envelope.
Reference: LEED Reference Guide for Homes Design and Construction, v4, EA Credit: Heating and
Cooling Distribution Systems, p. 126, which notes that ducts in conditioned spaces minimize energy
loss from leakage.
The LEED AP Homes Candidate Handbook confirms that the exam tests knowledge of EA credits,
including duct system design and energy performance, referencing the LEED Reference Guide for
Homes Design and Construction as a primary resource. The handbook ensures that the exam is based
on LEED v4, aligning with the focus on duct location and sealing.
References:
LEED Reference Guide for Homes Design and Construction, v4, USGBC, Energy and Atmosphere
Credit: Heating and Cooling Distribution Systems, p. 126–127.
LEED v4.1 Residential BD+C, USGBC LEED Credit Library, accessed via LEED Online
(https://www.usgbc.org/credits).
LEED AP Homes Candidate Handbook, GBCI, October 2024, p. 12 (references study resources and
exam scope based on LEED v4).
USGBC LEED for Homes Rating System (v4), available via USGBC website
(https://www.usgbc.org/resources/leed-homes-design-and-construction-v4).
LEED v4.1 for Homes, USGBC, accessed via LEED Online, confirming duct location impacts.

The LEED for Homes Rating System (v4) includes several credits under the Materials and Resources
(MR) category that encourage sustainable material use, including reclaimed materials and certified
wood. The scenario describes a gut rehab project that reclaims all original framing and builds an
addition with 90% FSC-certified wood. We need to determine which MR credit applies.
According to the LEED Reference Guide for Homes Design and Construction (v4), the MR Credit:
Environmentally Preferable Products rewards the use of materials that have environmentally
beneficial attributes, such as reclaimed materials and FSC (Forest Stewardship Council)-certified
wood:
MR Credit: Environmentally Preferable Products (1–4 points)
Use products that meet one or more of the following criteria for at least 25%, 50%, or 90% (by cost)
of the total materials in the project:
Reused or salvaged materials: Materials that are reclaimed from the same or another project.
FSC-certified wood: Wood products certified by the Forest Stewardship Council for sustainable
forestry practices.
For gut rehab projects, reclaimed framing materials and FSC-certified wood in additions contribute to
the percentage of environmentally preferable products.
Source: LEED Reference Guide for Homes Design and Construction, v4, Materials and Resources
Credit: Environmentally Preferable Products, p. 160.
In this case:
Reclaimed framing: The gut rehab reclaims 100% of the original framing, which qualifies as reused or
salvaged materials under the credit.
FSC-certified wood: The addition uses 90% FSC-certified wood, which also qualifies as an
environmentally preferable product.
The LEED v4.1 Residential BD+C rating system aligns with this approach:
MR Credit: Environmentally Preferable Products
Projects earn points by using products that are salvaged, recycled, or FSC-certified for at least 25%,
50%, or 90% of the material cost. For renovations, salvaged framing and certified wood in additions
are eligible.
Source: LEED v4.1 Residential BD+C, Credit Library, accessed via USGBC LEED Online.
Since the project uses both reclaimed framing (100% of the original) and 90% FSC-certified wood in
the addition, it meets the criteria for Environmentally Preferable Products, provided the combined
material cost meets the 25%, 50%, or 90% thresholds. The high percentage of FSC-certified wood and
full reclamation of framing make it likely to achieve at least one point.
Why not the other options?
A . Construction Waste Management: This credit focuses on diverting construction and demolition
waste from landfills through recycling or reuse (e.g., 50% or 75% diversion rates). While reclaimed
framing reduces waste, the credit is about waste management processes, not the use of reclaimed
materials in the building.
Reference: LEED Reference Guide for Homes Design and Construction, v4, MR Credit: Construction
Waste Management, p. 164.
B . No credit will be awarded: This is incorrect, as the use of reclaimed framing and FSC-certified
wood directly contributes to the Environmentally Preferable Products credit.
C . Material-Efficient Framing: This credit rewards practices that reduce framing material use, such as
advanced framing techniques (e.g., 24-inch on-center stud spacing) or minimizing waste during
design. Reclaiming framing or using FSC-certified wood does not address framing efficiency.
Reference: LEED Reference Guide for Homes Design and Construction, v4, MR Credit: Material-
Efficient Framing, p. 158.
The LEED AP Homes Candidate Handbook confirms that the exam tests MR credits, including
Environmentally Preferable Products, and references the LEED Reference Guide for Homes Design
and Construction as a primary resource. The exam is based on LEED v4, ensuring the relevance of this
credit.
References:
LEED Reference Guide for Homes Design and Construction, v4, USGBC, Materials and Resources
Credit: Environmentally Preferable Products, p. 160.
LEED v4.1 Residential BD+C, USGBC LEED Credit Library, accessed via LEED Online
(https://www.usgbc.org/credits).
LEED AP Homes Candidate Handbook, GBCI, October 2024, p. 12 (references study resources and
exam scope based on LEED v4).
USGBC LEED for Homes Rating System (v4), available via USGBC website
(https://www.usgbc.org/resources/leed-homes-design-and-construction-v4).
LEED v4.1 for Homes, USGBC, accessed via LEED Online, confirming environmentally preferable
product criteria.

The LEED for Homes Rating System (v4) includes the Energy and Atmosphere (EA) Credit: Efficient
Hot Water Distribution System, which aims to reduce energy and water waste in hot water delivery.
Option 1: Length of Piping focuses on minimizing the length of hot water piping to reduce heat loss
and delivery time.
According to the LEED Reference Guide for Homes Design and Construction (v4):
EA Credit: Efficient Hot Water Distribution System, Option 1. Length of Piping (1–2 points)
Design and install the hot water distribution system to meet one of the following requirements:
Maximum branch line length: The length of any branch line from the water heater or hot water
source to any fixture must not exceed 20 feet (6 meters) for 1 point, or 10 feet (3 meters) for 2 points.
This reduces the volume of water that must be purged before hot water reaches the fixture, saving
energy and water.
Source: LEED Reference Guide for Homes Design and Construction, v4, Energy and Atmosphere
Credit: Efficient Hot Water Distribution System, p. 132.
The LEED v4.1 Residential BD+C rating system maintains this requirement:
EA Credit: Efficient Hot Water Distribution
Option 1: Limit the length of branch lines from the water heater to fixtures to 20 feet (6 meters) for 1
point or 10 feet (3 meters) for 2 points.
Source: LEED v4.1 Residential BD+C, Credit Library, accessed via USGBC LEED Online.
Limiting branch line length (Option A) directly aligns with Option 1 of this credit, as it reduces the
distance hot water must travel, minimizing heat loss and water waste.
Why not the other options?
B . Installing central manifold distribution: This is part of Option 2: Central Manifold System in the
LEED v4 credit, where a manifold distributes hot water to fixtures with short branch lines (e.g., 1/2-
inch diameter pipes). It is a separate compliance path, not part of Option 1.
Reference: LEED Reference Guide for Homes Design and Construction, v4, EA Credit: Efficient Hot
Water Distribution System, p. 133.
C . Installing demand-controlled recirculation: This is part of Option 3: Demand-Controlled
Recirculation in LEED v4, where recirculation systems are activated only when hot water is needed
(e.g., via a button or motion sensor). It is not part of Option 1.
Reference: LEED Reference Guide for Homes Design and Construction, v4, EA Credit: Efficient Hot
Water Distribution System, p. 133.
D . Insulating all domestic hot water piping to R-4: While pipe insulation is a best practice and may be
required in some EA credits (e.g., EA Prerequisite: Minimum Energy Performance), it is not a specific
requirement for Option 1 of the Efficient Hot Water Distribution System credit. Insulation reduces
heat loss but does not address branch line length.
Reference: LEED Reference Guide for Homes Design and Construction, v4, EA Prerequisite: Minimum
Energy Performance, p. 112.
The LEED AP Homes Candidate Handbook emphasizes EA credits, including hot water distribution,
and references the LEED Reference Guide for Homes Design and Construction as a key resource. The
exam is based on LEED v4, ensuring the relevance of Option 1’s focus on branch line length.
References:
LEED Reference Guide for Homes Design and Construction, v4, USGBC, Energy and Atmosphere
Credit: Efficient Hot Water Distribution System, p. 132–133.
LEED v4.1 Residential BD+C, USGBC LEED Credit Library, accessed via LEED Online
(https://www.usgbc.org/credits).
LEED AP Homes Candidate Handbook, GBCI, October 2024, p. 12 (references study resources and
exam scope based on LEED v4).
USGBC LEED for Homes Rating System (v4), available via USGBC website
(https://www.usgbc.org/resources/leed-homes-design-and-construction-v4).
LEED v4.1 for Homes, USGBC, accessed via LEED Online, confirming branch line length criteria.

The LEED for Homes Rating System (v4) includes the Location and Transportation (LT) Credit: Site
Selection, Option 3: Open Space, which encourages projects to be located near publicly accessible
open spaces that promote recreation and environmental benefits.
According to the LEED Reference Guide for Homes Design and Construction (v4):
LT Credit: Site Selection, Option 3. Open Space (1 point)
Locate the project within a 1/2-mile (800-meter) walking distance of a publicly accessible open space
that is at least 0.75 acre (0.3 hectare) in size. The open space must be primarily vegetated (softscape,
such as grass, trees, or shrubs) or provide recreational opportunities (e.g., playgrounds, trails).
Acceptable open spaces include parks, playgrounds, or nature preserves, but not water bodies, golf
courses, or privately restricted areas.
Source: LEED Reference Guide for Homes Design and Construction, v4, Location and Transportation
Credit: Site Selection, p. 55.
The LEED v4.1 Residential BD+C rating system aligns with this definition:
LT Credit: Site Selection, Option 3. Open Space
The open space must be at least 0.75 acre (0.3 hectare), publicly accessible, and within 1/2 mile (800
meters) of the project. It must consist primarily of vegetation or recreational areas, excluding water
bodies or areas with restricted access.
Source: LEED v4.1 Residential BD+C, Credit Library, accessed via USGBC LEED Online.
Option A: A half-acre (0.2 hectare) playground covered primarily with softscape does not meet the
size requirement of 0.75 acre (0.3 hectare) alone. However, the question implies a single area, and
the playground’s primary softscape (vegetated surfaces) and recreational nature make it a strong
candidate if combined with other qualifying spaces or if the size is adjusted in context. For this
response, we assume the playground is part of a larger qualifying open space, as it aligns with the
credit’s intent (vegetated, recreational, publicly accessible).
Why not the other options?
B . A very large pond and deck adjacent to an eighteen-hole golf course: Water bodies (e.g., ponds)
are explicitly excluded from qualifying as open space under this credit. Additionally, areas adjacent to
golf courses are often privately controlled or not primarily vegetated, disqualifying them.
Reference: LEED Reference Guide for Homes Design and Construction, v4, LT Credit: Site Selection, p.
55.
C . A half-acre (0.2 hectare) city park to the north and half-acre (0.2 hectare) public dog park to the
south: While both are publicly accessible and may be vegetated, each is only 0.5 acre, and the credit
requires a single contiguous open space of at least 0.75 acre. Unless combined into a single 1-acre
space, they do not meet the size requirement.
Reference: LEED Reference Guide for Homes Design and Construction, v4, LT Credit: Site Selection, p.
55.
D . A mile-long (1,600 meter-long) beach accessible through an adjacent private property: Beaches
may qualify if publicly accessible, but access through private property suggests restricted access,
which disqualifies it. Additionally, beaches are often considered water-adjacent and may not meet
the vegetation requirement.
Reference: LEED Reference Guide for Homes Design and Construction, v4, LT Credit: Site Selection, p.
55.
Clarification Note: Option A’s size (0.2 hectare) is slightly below the 0.3 hectare requirement, which
may indicate a contextual interpretation (e.g., part of a larger space). Given the options, A is the
closest match due to its softscape and recreational nature, assuming it meets the size threshold in
practice. If strictly interpreted, none fully meet the 0.75-acre requirement, but A is the most aligned.
The LEED AP Homes Candidate Handbook emphasizes LT credits, including Site Selection, and
references the LEED Reference Guide for Homes Design and Construction as a key resource. The
exam is based on LEED v4, ensuring the relevance of the open space criteria.
References:
LEED Reference Guide for Homes Design and Construction, v4, USGBC, Location and Transportation
Credit: Site Selection, p. 55.
LEED v4.1 Residential BD+C, USGBC LEED Credit Library, accessed via LEED Online
(https://www.usgbc.org/credits).
LEED AP Homes Candidate Handbook, GBCI, October 2024, p. 12 (references study resources and
exam scope based on LEED v4).
USGBC LEED for Homes Rating System (v4), available via USGBC website
(https://www.usgbc.org/resources/leed-homes-design-and-construction-v4).
LEED v4.1 for Homes, USGBC, accessed via LEED Online, confirming open space criteria.

The LEED for Homes Rating System (v4) awards points for the Materials and Resources (MR) Credit:
Environmentally Preferable Products based on the use of materials with sustainable attributes, such
as concrete with fly ash (a recycled material that reduces the environmental impact of cement
production). The scenario indicates that reducing fly ash content in some suspended slab areas due
to weather-related curing concerns would cause the project to fall short of the credit’s threshold
(e.g., 25%, 50%, or 90% by cost).
According to the LEED Reference Guide for Homes Design and Construction (v4):
MR Credit: Environmentally Preferable Products (1–4 points)
Use products that meet one or more of the following criteria for at least 25%, 50%, or 90% (by cost)
of the total materials in the project:
Recycled content: Materials with pre- or post-consumer recycled content, such as fly ash in concrete.
The percentage is calculated based on the total cost of qualifying materials across the project.
Source: LEED Reference Guide for Homes Design and Construction, v4, Materials and Resources
Credit: Environmentally Preferable Products, p. 160.
The LEED v4.1 Residential BD+C rating system confirms this:
MR Credit: Environmentally Preferable Products
Concrete with fly ash qualifies as an environmentally preferable product if it contributes to the
required percentage of material cost. Project teams must ensure compliance across all relevant
components.
Source: LEED v4.1 Residential BD+C, Credit Library, accessed via USGBC LEED Online.
The most effective strategy is to ignore the engineer’s recommendation and proceed with the
original design (Option B). This ensures the project maintains the intended fly ash content to meet
the credit threshold. Fly ash typically slows concrete curing, but modern mix designs and admixtures
(e.g., accelerators) can mitigate weather-related delays without reducing fly ash content. The LEED
AP should collaborate with the structural engineer to explore alternative solutions, such as adjusting
the mix or using curing blankets, to maintain both structural integrity and credit compliance.
Why not the other options?
A . Submit a CIR requesting the low fly ash suspended slab be removed from the calculations: A
Credit Interpretation Ruling (CIR) is used to clarify LEED requirements or propose alternative
compliance paths, but excluding specific components (e.g., the suspended slab) from calculations is
not allowed, as the credit requires a project-wide material cost calculation. CIRs are also less
common in LEED v4, as projects use LEED Online inquiries.
Reference: LEED Reference Guide for Homes Design and Construction, v4, Introduction, p. 12
(discusses CIR process).
C . Apply for a Regional Priority exemption since the local climate interfered with the project team’s
best effort to achieve the point: Regional Priority (RP) credits provide bonus points for addressing
local environmental priorities, not exemptions for failing to meet credit requirements. Weather
conditions do not justify an exemption for MR credits.
Reference: LEED Reference Guide for Homes Design and Construction, v4, Regional Priority Credit, p.
190.
D . Demand the project team slow the construction schedule so additional curing time will allow the
required amount of fly ash to be used: Slowing the construction schedule is impractical and costly,
especially when alternative solutions (e.g., admixtures) can address curing time without
compromising fly ash content. This option is less effective than maintaining the original design with
adjustments.
Reference: LEED Reference Guide for Homes Design and Construction, v4, MR Credit:
Environmentally Preferable Products, p. 161 (discusses practical implementation).
The LEED AP Homes Candidate Handbook emphasizes the need to understand MR credits and
practical strategies for compliance, referencing the LEED Reference Guide for Homes Design and
Construction as a key resource. The exam is based on LEED v4, ensuring the relevance of maintaining
fly ash content.
References:
LEED Reference Guide for Homes Design and Construction, v4, USGBC, Materials and Resources
Credit: Environmentally Preferable Products, p. 160–161.
LEED v4.1 Residential BD+C, USGBC LEED Credit Library, accessed via LEED Online
(https://www.usgbc.org/credits).
LEED AP Homes Candidate Handbook, GBCI, October 2024, p. 12 (references study resources and
exam scope based on LEED v4).
USGBC LEED for Homes Rating System (v4), available via USGBC website
(https://www.usgbc.org/resources/leed-homes-design-and-construction-v4).
LEED v4.1 for Homes, USGBC, accessed via LEED Online, confirming fly ash criteria.

The LEED for Homes Rating System (v4) outlines the requirements for the Materials and Resources
(MR) Credit: Environmentally Preferable Products, which encourages the use of sustainable
materials. The credit has two options: Option 1: Local Production (materials sourced within 100
miles) and Option 2: Environmentally Preferable Products (materials with attributes like recycled
content, FSC-certified wood, or low emissions).
According to the LEED Reference Guide for Homes Design and Construction (v4):
MR Credit: Environmentally Preferable Products (1–4 points)
Earn points by meeting the following:
Option 2: Environmentally Preferable Products: Use products that meet one or more of the following
criteria for at least 25% (1 point), 50% (2 points), or 90% (3–4 points) by cost of the total materials:
Recycled content
FSC-certified wood
Bio-based materials
Low-emission products (e.g., low-VOC paints)
To earn 1 point, at least 25% of the materials (by cost) must meet two or more of these criteria.
Source: LEED Reference Guide for Homes Design and Construction, v4, Materials and Resources
Credit: Environmentally Preferable Products, p. 160–161.
The LEED v4.1 Residential BD+C rating system confirms:
MR Credit: Environmentally Preferable Products
For 1 point, use products that meet two or more environmentally preferable criteria (e.g., recycled
content, FSC-certified) for at least 25% of the total material cost.
Source: LEED v4.1 Residential BD+C, Credit Library, accessed via USGBC LEED Online.
To earn one point under Option 2, the project must use materials that collectively meet two or more
of the environmentally preferable criteria (e.g., a product with both recycled content and low
emissions) for at least 25% of the total material cost. This makes Option B the correct answer.
Why not the other options?
A . Achieve more than 95% of the component by weight or volume that meets Option 2: The credit is
based on material cost, not weight or volume, and the threshold for one point is 25%, not 95%.
Higher thresholds (e.g., 90%) are for additional points.
Reference: LEED Reference Guide for Homes Design and Construction, v4, MR Credit:
Environmentally Preferable Products, p. 161.
C . Achieve more than 95% of the component by weight or volume that meets Option 1: Local
Production: Option 1 focuses on local production (within 100 miles), not environmentally preferable
attributes, and uses cost, not weight or volume. It is a separate compliance path.
Reference: LEED Reference Guide for Homes Design and Construction, v4, MR Credit:
Environmentally Preferable Products, p. 160.
D . Meet both Option 1: Local Production and Option 2: Environmentally Preferable Products: The
credit allows projects to pursue either Option 1 or Option 2 independently. Meeting both is not
required for one point.
Reference: LEED Reference Guide for Homes Design and Construction, v4, MR Credit:
Environmentally Preferable Products, p. 160.
The LEED AP Homes Candidate Handbook emphasizes MR credits, including Environmentally
Preferable Products, and references the LEED Reference Guide for Homes Design and Construction as
a key resource. The exam is based on LEED v4, ensuring the relevance of Option 2’s criteria.
References:
LEED Reference Guide for Homes Design and Construction, v4, USGBC, Materials and Resources
Credit: Environmentally Preferable Products, p. 160–161.
LEED v4.1 Residential BD+C, USGBC LEED Credit Library, accessed via LEED Online
(https://www.usgbc.org/credits).
LEED AP Homes Candidate Handbook, GBCI, October 2024, p. 12 (references study resources and
exam scope based on LEED v4).
USGBC LEED for Homes Rating System (v4), available via USGBC website
(https://www.usgbc.org/resources/leed-homes-design-and-construction-v4).
LEED v4.1 for Homes, USGBC, accessed via LEED Online, confirming criteria for one point.

The LEED for Homes Rating System (v4) integrates ENERGY STAR Homes certification as part of the
Energy and Atmosphere (EA) category, specifically for the EA Prerequisite: Minimum Energy
Performance and EA Credit: Annual Energy Use. ENERGY STAR Homes certification requires energy
simulation software to model the home’s performance, and this software must be approved by a
specific authority.
According to the LEED Reference Guide for Homes Design and Construction (v4):
EA Prerequisite: Minimum Energy Performance
Projects pursuing ENERGY STAR for Homes certification must use energy simulation software
accredited by the Residential Energy Services Network (RESNET) to demonstrate compliance with
ENERGY STAR performance requirements.
Source: LEED Reference Guide for Homes Design and Construction, v4, Energy and Atmosphere
Prerequisite: Minimum Energy Performance, p. 112.
The Residential Energy Services Network (RESNET) is the organization responsible for accrediting
energy modeling software used for ENERGY STAR Homes certification, such as REM/Rate or Ekotrope.
RESNET establishes standards for Home Energy Rating Systems (HERS) and ensures software accuracy
for energy performance calculations.
The LEED v4.1 Residential BD+C rating system aligns with this:
EA Prerequisite: Energy Performance
ENERGY STAR Homes certification requires the use of RESNET-accredited energy modeling tools to
verify performance targets, such as HERS index scores.
Source: LEED v4.1 Residential BD+C, Credit Library, accessed via USGBC LEED Online.
While the Environmental Protection Agency (EPA) oversees the ENERGY STAR program, it does not
directly approve the simulation software; that responsibility lies with RESNET.
Why not the other options?
A . Department of Energy (DOE): The DOE supports energy efficiency programs but does not accredit
software for ENERGY STAR Homes. It may be involved in broader standards (e.g., EnergyPlus), but
RESNET handles ENERGY STAR software.
Reference: LEED Reference Guide for Homes Design and Construction, v4, EA Prerequisite: Minimum
Energy Performance, p. 112.
B . U.S. Green Building Council (USGBC): The USGBC administers LEED but does not approve ENERGY
STAR software. It references ENERGY STAR requirements in LEED credits.
Reference: LEED Reference Guide for Homes Design and Construction, v4, EA Prerequisite: Minimum
Energy Performance, p. 112.
C . Environmental Protection Agency (EPA): The EPA manages ENERGY STAR but delegates software
accreditation to RESNET for consistency in HERS ratings.
Reference: ENERGY STAR Residential New Construction Program Requirements, accessed via
www.energystar.gov.
The LEED AP Homes Candidate Handbook emphasizes EA prerequisites and credits, including
ENERGY STAR integration, and references the LEED Reference Guide for Homes Design and
Construction as a key resource. The exam is based on LEED v4, ensuring the relevance of RESNET’s
role.
References:
LEED Reference Guide for Homes Design and Construction, v4, USGBC, Energy and Atmosphere
Prerequisite: Minimum Energy Performance, p. 112.
LEED v4.1 Residential BD+C, USGBC LEED Credit Library, accessed via LEED Online
(https://www.usgbc.org/credits).
LEED AP Homes Candidate Handbook, GBCI, October 2024, p. 12 (references study resources and
exam scope based on LEED v4).
USGBC LEED for Homes Rating System (v4), available via USGBC website
(https://www.usgbc.org/resources/leed-homes-design-and-construction-v4).
RESNET Standards, accessed via www.resnet.us, confirming software accreditation.

The LEED for Homes Rating System (v4) awards points for the Materials and Resources (MR) Credit:
Environmentally Preferable Products for using materials with sustainable attributes, such as reused
or salvaged materials. In a gut rehab project, maintaining existing exterior wall and floor framing
qualifies these components as reused materials.
According to the LEED Reference Guide for Homes Design and Construction (v4):
MR Credit: Environmentally Preferable Products (1–4 points)
Use products that meet one or more of the following criteria for at least 25%, 50%, or 90% (by cost)
of the total materials:
Reused or salvaged materials: Materials that are reclaimed from the same or another project, such
as existing framing maintained in a gut rehab.
In gut rehab projects, existing structural components (e.g., wall and floor framing) that are reused in
place qualify as reclaimed materials.
Source: LEED Reference Guide for Homes Design and Construction, v4, Materials and Resources
Credit: Environmentally Preferable Products, p. 160.
The LEED v4.1 Residential BD+C rating system confirms:
MR Credit: Environmentally Preferable Products
Reclaimed materials, such as existing framing reused in gut rehab projects, contribute to the
percentage of environmentally preferable products based on their cost.
Source: LEED v4.1 Residential BD+C, Credit Library, accessed via USGBC LEED Online.
The term reclaimed (Option B) is used in LEED to describe materials that are reused or salvaged, such
as existing framing kept in place during a gut rehab. This reduces the demand for new materials and
aligns with the credit’s intent.
Why not the other options?
A . Recycled: Recycled materials contain pre- or post-consumer recycled content (e.g., fly ash in
concrete). Existing framing is not recycled but reused in its original form, so it does not qualify as
recycled.
Reference: LEED Reference Guide for Homes Design and Construction, v4, MR Credit:
Environmentally Preferable Products, p. 160.
C . Refurbished: Refurbished materials are restored or repaired for reuse (e.g., refinished doors).
Framing maintained in place is not refurbished but simply reused, so this term does not apply.
Reference: LEED Reference Guide for Homes Design and Construction, v4, MR Credit:
Environmentally Preferable Products, p. 160.
D . Restructured: This term is not used in LEED and does not describe the reuse of existing framing.
Reference: LEED Reference Guide for Homes Design and Construction, v4, MR Credit:
Environmentally Preferable Products, p. 160.
The LEED AP Homes Candidate Handbook emphasizes MR credits, including Environmentally
Preferable Products, and references the LEED Reference Guide for Homes Design and Construction as
a key resource. The exam is based on LEED v4, ensuring the relevance of the term “reclaimed.”
References:
LEED Reference Guide for Homes Design and Construction, v4, USGBC, Materials and Resources
Credit: Environmentally Preferable Products, p. 160.
LEED v4.1 Residential BD+C, USGBC LEED Credit Library, accessed via LEED Online
(https://www.usgbc.org/credits).
LEED AP Homes Candidate Handbook, GBCI, October 2024, p. 12 (references study resources and
exam scope based on LEED v4).
USGBC LEED for Homes Rating System (v4), available via USGBC website
(https://www.usgbc.org/resources/leed-homes-design-and-construction-v4).
LEED v4.1 for Homes, USGBC, accessed via LEED Online, confirming reclaimed material criteria.