FireApproved

Findings

Under-deck mesh belongs on the vertical plane to grade, not under the boards

installation-mistake

Screening laid horizontally under deck boards does not close the ember path from the side. The IBHS Wildfire Prepared Home standard calls for corrosion-resistant metal mesh to fully enclose the outer edge of the space beneath a deck down to the ground.

Two deck sections. One encloses the outer edge from walking surface to grade. The other lays mesh horizontally under the boards and leaves the side open.
FA Exhibit DET-005. Under-deck mesh — outer edge versus under the boards. After IBHS Wildfire Prepared Home technical standard and FEMA P-737. Illustrative — not a construction document. Verify with your building official. CC BY 4.0.

As of 2026-08-23. JSON (CC BY 4.0)

Sources

Under-deck mesh belongs on the vertical plane to grade, not under the boards. FireApproved. https://fireapproved.com/findings/under-deck-horizontal-mesh/. As of 2026-08-23.