---
kind: "section"
citation: "24 C.F.R. § 3285.204"
title: "24"
number: "3285.204"
heading: "Ground moisture control."
url: "https://uscodex.org/cfr/24/3285.204"
---

# §3285.204. Ground moisture control.

- (a) **Vapor retarder.** If the space under the home is to be enclosed with skirting or other materials, a vapor retarder must be installed to cover the ground under the home, unless the home is installed in an arid region with dry soil conditions.
- (b) **Vapor retarder material.** A minimum of six mil polyethylene sheeting or its equivalent must be used.
- (c) **Proper installation.**
  - (1) The entire area under the home must be covered with the vapor retarder, as noted in [§ 3285.204(a)](#a), except for areas under open porches, decks, and recessed entries. Joints in the vapor retarder must be overlapped at least 12 inches.
  - (2) The vapor retarder may be placed directly beneath footings, or otherwise installed around or over footings placed at grade, and around anchors or other obstructions.
  - (3) Any voids or tears in the vapor retarder must be repaired. At least one repair method must be provided in the manufacturer's installation instructions.

## Notes

### Authority

Authority: 42 U.S.C. 3535(d), 5403, 5404, and 5424.

### Source

Source: 72 FR 59362, Oct. 19, 2007, unless otherwise noted.