USGBC LEED-AP-Homes Practice Test Questions Answers

TheLEED for Homes Rating System (v4)includes theIndoor Environmental Quality (EQ) Credit: Radon Control, which promotes radon-resistant construction techniques to mitigate the health risks of radon gas, a naturally occurring radioactive gas that can accumulate in homes.

According to theLEED Reference Guide for Homes Design and Construction (v4):

EQ Credit: Radon Control (1 point)

Install a passive or active radon-resistant system, including a vent pipe extending from below the foundation (e.g., sub-slab or crawlspace) to the roof to exhaust radon gases before they enter the home. This is a primary radon-resistant construction technique.

Source: LEED Reference Guide for Homes Design and Construction, v4, Indoor Environmental Quality Credit: Radon Control, p. 150.

TheLEED v4.1 Residential BD+Crating system confirms:

EQ Credit: Radon Control

A vent pipe to exhaust gases from under the home (e.g., sub-slab depressurization system) is a key radon-resistant technique, preventing radon entry into living spaces.

Source: LEED v4.1 Residential BD+C, Credit Library, accessed via USGBC LEED Online.

The correct answer isvent pipe to exhaust gases from under the home(Option A), as this is a standard radon-resistant technique, typically involving a sub-slab depressurization system with a vent pipe.

Why not the other options?

TheLEED for Homes Rating System (v4)integrates ENERGY STAR Homes certification as part of theEnergy and Atmosphere (EA)category, specifically for theEA Prerequisite: Minimum Energy PerformanceandEA 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 theLEED 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.

TheResidential 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.

TheLEED v4.1 Residential BD+Crating 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 theEnvironmental 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?

TheLEED for Homes Rating System (v4)addresses outdoor water use in theWater Efficiency (WE) Credit: Outdoor Water Use, which promotes strategies to reduce irrigation needs, particularly through plant selection.

According to theLEED Reference Guide for Homes Design and Construction (v4):

WE Credit: Outdoor Water Use (1–4 points)

Use native or adapted plants with low water requirements to reduce outdoor water consumption. These plants are suited to the local climate and require less irrigation compared to conventional turf or non-native species.

Source: LEED Reference Guide for Homes Design and Construction, v4, Water Efficiency Credit: Outdoor Water Use, p. 98.

TheLEED v4.1 Residential BD+Crating system confirms:

WE Credit: Outdoor Water Use

Selecting native and adapted plants is an effective strategy to minimize irrigation needs, contributing to points by reducing outdoor water consumption.

Source: LEED v4.1 Residential BD+C, Credit Library, accessed via USGBC LEED Online.

The correct answer isnative and adapted plants(Option D), as these reduce irrigation demand by being well-suited to local conditions, directly aligning with the credit’s intent.

Why not the other options?

TheLEED for Homes Rating System (v4)requires blower door testing in theEnergy and Atmosphere (EA) Credit: Air Infiltrationto measure envelope leakage, expressed as air changes per hour (ACH) at a specific pressure differential.

According to theLEED Reference Guide for Homes Design and Construction (v4):

EA Credit: Air Infiltration (1–3 points)

Conduct a blower door test to measure envelope leakage in air changes per hour (ACH) at a pressure differential of 50 pascals (Pa). This standardizes the measurement of air tightness across projects.

Source: LEED Reference Guide for Homes Design and Construction, v4, Energy and Atmosphere Credit: Air Infiltration, p. 124.

TheLEED v4.1 Residential BD+Crating system confirms:

EA Credit: Air Infiltration

Envelope leakage is measured using a blower door test at 50 pascals, reported as ACH50, to assess the airtightness of the building envelope.

Source: LEED v4.1 Residential BD+C, Credit Library, accessed via USGBC LEED Online.

The correct answer is50 pascals(Option B), as this is the standard pressure differential for measuring ACH in LEED for Homes.

Why not the other options?

TheLEED for Homes Rating System (v4)includes theIndoor Environmental Quality (EQ) Credit: Enhanced Garage Pollutant Protection, which aims to prevent garage pollutants (e.g., vehicle exhaust, chemicals) from entering conditioned living spaces.

According to theLEED Reference Guide for Homes Design and Construction (v4):

EQ Credit: Enhanced Garage Pollutant Protection (1–2 points)

To achieve the maximum points (2 points), use a detached garage, as it physically separates the garage from conditioned spaces, eliminating the risk of pollutant transfer. Other strategies, such as sealing the garage-conditioned space interface or installing exhaust fans, earn fewer points.

Source: LEED Reference Guide for Homes Design and Construction, v4, Indoor Environmental Quality Credit: Enhanced Garage Pollutant Protection, p. 149.

TheLEED v4.1 Residential BD+Crating system confirms:

EQ Credit: Enhanced Garage Pollutant Protection

A detached garage is the most effective strategy, earning the maximum 2 points by preventing any pollutant transfer from the garage to the home’s conditioned spaces.

Source: LEED v4.1 Residential BD+C, Credit Library, accessed via USGBC LEED Online.

The correct answer isusing a detached garage(Option C), as it achieves the maximum points by eliminating the risk of pollutant infiltration.

Why not the other options?