Discuss US Green Building Council LEED-AP-Homes Exam Topic 7 Question 18

Which of the following measures is a radon-resistant construction technique?

AVent pipe to exhaust gases from under the home

BPressurized basement or crawlspace to prevent gases from entering the home

CPerforated foundation slab to allow air circulation

DContinuously operating bath fans to remove gases from inside the home

Suggested Answer: A

The LEED for Homes Rating System (v4) includes the Indoor 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 the LEED 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.

The LEED v4.1 Residential BD+C rating 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 is vent 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?

B . Pressurized basement or crawlspace to prevent gases from entering the home: Pressurization can reduce infiltration but is not a standard radon-resistant technique; depressurization (via venting) is preferred.

C . Perforated foundation slab to allow air circulation: Perforated slabs are not a recognized radon-resistant method; they may increase radon entry by allowing gas to flow into the home.

D . Continuously operating bath fans to remove gases from inside the home: Bath fans address general ventilation, not radon-specific mitigation, which requires sub-slab venting.

The LEED AP Homes Candidate Handbook emphasizes EQ credits, including radon control, 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 vent pipe systems.

References:

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

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 radon-resistant techniques.

Get Premium LEED-AP-Homes Questions as Interactive Web-Based Practice Test or PDF Real Exam Format Detailed Explanations Instant Access Get Your Practice Test

23 comments · newest first

Torie 1 day ago

I think A is the right choice.

Elliot 6 days ago

A is straightforward. It’s a proven method.

Aleta 12 days ago

I feel like B could work, but A is more reliable.

Lavina 17 days ago

A is definitely radon-resistant. It’s a must for homes.

Graciela 22 days ago

D is helpful, but not a construction technique.

Art 27 days ago

C is interesting, but not as effective as A.

Jestine 1 month ago

B sounds good too, but I prefer A.

Irma 1 month ago

I agree, A makes sense. It directly exhausts gases.

Giuseppe 1 month ago

I think A is the best choice. Vent pipes are crucial.

Alida 2 months ago

A and B are the most common methods used for radon resistance.

Margery 2 months ago

D) Continuously operating bath fans? Not sure that’s effective for radon.

Ettie 2 months ago

Wait, are we sure C) Perforated foundation slab really helps? Sounds odd.

Raymon 2 months ago

I think B) Pressurized basement is also a solid choice!

Gerald 2 months ago

A) Vent pipe to exhaust gases is definitely a radon-resistant technique.

Brock 2 months ago

Vent pipes are the standard for radon mitigation, no doubt!

Luz 3 months ago

Perforated slabs? That's new to me, but I guess it makes sense!

Marshall 3 months ago

Wait, are bath fans really effective for radon? Sounds odd.

Alexis 3 months ago

I thought pressurized spaces were more for moisture control?

Jesusita 3 months ago

A vent pipe is definitely a radon-resistant technique!

Latricia 3 months ago

I definitely remember the perforated slab being mentioned in class, but I thought it was more about drainage than radon resistance.

Alexia 3 months ago

I feel like the continuously operating bath fans might help with indoor air quality, but I'm not sure if they actually prevent radon from entering.

Golda 4 months ago

I remember practicing a question about pressurized spaces, but I can't recall if that's specifically for radon.

Hobert 4 months ago

I think the vent pipe option sounds familiar, but I'm not entirely sure if it's the only radon-resistant technique.

US Green Building Council LEED-AP-Homes Exam - Topic 7 Question 18 Discussion