FA Exhibit DET-003

The Type X exception: wood siding over 5/8" exterior gypsum

An exterior wall section shows framing, one layer of five-eighths-inch Type X exterior gypsum sheathing, and exterior covering or cladding in that order. A bracket marks the covering extent from the top of the foundation to the roof, with termination at two-inch nominal blocking or the underside of an enclosed soffit. — FA Exhibit DET-003. The Type X exterior-wall exception. AFTER ORSC R327.3.3 EXCEPTION 1 & R327.3.3.1 · FEMA P-737 §4.3 CONTEXT · PARENT: WAL-100. Illustrative — not a construction document. Verify with your building official. CC BY 4.0.

Technical review: Grayson Graham. Last verified 2026-08-25. JSON

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