D08 · Passive radon system in new construction

ALT TEXT
Labeled new-construction diagram showing a passive under-slab radon vent, no operating fan, a fan-ready provision, outdoor discharge, and a dated Iowa code-status note.

LONG DESCRIPTION
A new-construction basement cross-section shows a prepared collection layer beneath the slab and a vertical passive vent route to outdoor discharge. No active fan or active-system fan monitor is shown; a fan-ready provision is indicated conceptually. The Iowa overlay states that Iowa Acts Chapter 1124 directs the State Building Code Commissioner to adopt a passive method from 2021 IRC Appendix AF, while the published July 8, 2026 edition of Iowa Administrative Code chapter 481—301 still deletes residential-code appendices AA through CH. The figure does not state that the statutory direction alone makes Appendix AF enforceable for a specific project.

Source basis: Iowa Acts Chapter 1124 (approved May 19, 2026); Iowa Administrative Code 481—Chapter 301 dated July 8, 2026; ANSI/AARST CCAH-2020-0523 catalogue listing. Verified July 24, 2026.
