Concrete flat tile reroof in Clay County, Florida (design wind about 130-140 mph), 4:12 hip roof.

Expect red tags on three items minimum:

1. Underlayment (FBC 1507.3.3 / FRSA/TRI Manual): Clay County (HVHZ-adjacent, 130–140 mph) requires two layers of underlayment for concrete tile on slopes < 5:12. Layer 1: ASTM D226 Type II (#30) or D4869 Type IV, cap-nailed 12" o.c. Layer 2: Self-adhering polymer-modified bitumen (ASTM D1970) over the entire deck. Single-layer #30 felt fails code.*

1. Tile Attachment (FBC 1507.3.7 / FRSA/TRI Appendix B, Table 1B): For 130+ mph, 4:12 hip roof, two smooth-shank nails direct-to-deck is insufficient for field tiles. You need: Ring-shank nails (min 11 ga., 5/16" head, 1.5" penetration into deck) OR screws. Perimeter/edge tiles often require two fasteners + adhesive or three fasteners. * Smooth shank lacks withdrawal resistance at design pressure.

1. Hip/Ridge Installation (FBC 1507.3.8 / FRSA/TRI Ch. 7): Mortar-only is prohibited in High Velocity Hurricane Zones and 130+ mph zones. Requires mechanical attachment (stainless/coated screws or nails into a treated 2x nailer board anchored to framing) plus approved adhesive/mortar. No nailer board = no structural connection.

Other likely hits:

• Missing drip edge (FBC 1507.2.8.1).
• Missing secondary water barrier tape at deck seams (FBC 1507.3.3.2).
• Flashing details (valleys, walls) not per FRSA/TRI manual.

Fix before inspection:

1. Strip felt. Install SA membrane full deck. Re-install #30 cap-nailed.
2. Switch to ring-shank nails or screws per FRSA/TRI Table 1B for your tile profile/weight/zone.
3. Install pressure-treated 2x nailers at hips/ridges (strapped to trusses). Fasten hip/ridge tiles mechanically + adhesive.

Do not cover until Building Official approves underlayment and nailer installation.

You’re likely to get red-tagged for multiple serious code violations under the Florida Building Code (FBC), 7th Edition (2020), which governs Clay County. Here’s what will fail inspection — and why:

❌ Critical Violations Likely to Trigger Red-Tag:

1. #30 Felt Underlayment — Not Permitted for Tile Roofs in High-Wind Zones

• FBC 1507.3.2 requires minimum Type II underlayment (synthetic or self-adhering polymer-modified bitumen) for clay/concrete tile roofs in Wind Speed ≥ 110 mph (your area: 130–140 mph).
• #30 asphalt felt is prohibited in high-wind zones for tile roofs — it lacks sufficient tear resistance and uplift capacity.
• ✅ Correct: Use ASTM D226 Type II (or equivalent synthetic underlayment meeting FBC 1507.3.2 Exception 1) or self-adhering modified bitumen (e.g., Grace Ice & Water Shield HT or equivalent).

2. Tile Fastening — Insufficient and Improper

• FBC 1507.3.3: Concrete/clay tile must be fastened with corrosion-resistant nails (hot-dipped galvanized, stainless steel, or aluminum) minimum 11-gauge shank, minimum 1-1/4” penetration into framing (not just sheathing).
• Smooth-shank nails are not permitted — they lack pull-out resistance. Ring-shank or screw-shank nails required.
• Two nails per tile may be acceptable only if:
• Nails are properly sized and type (ring-shank, min. 11 ga),
• Penetration into rafter/truss (not just 15/32” OSB/plywood),
• And tile is not in a high-wind zone (which it is).
• ✅ Correct: Use two 11-gauge ring-shank nails per tile, minimum 1-1/4” embedment into framing. For hip/ridge, see below.

3. Hip/Ridge Tiles Set in Mortar Only — No Mechanical Fastening

• FBC 1507.3.4: Hip and ridge tiles must be mechanically fastened to the roof structure — mortar-only installation is prohibited in high-wind zones.
• Mortar alone cannot resist uplift forces at 130–140 mph winds. This is a known failure mode in hurricanes.
• ✅ Correct: Hip/ridge tiles must be nailed or screwed to a hip/ridge board (min. 1x4 nailer) or directly to framing with corrosion-resistant fasteners, in addition to mortar bed (if used). Mortar is for bedding/sealing — not primary attachment.

4. No Hip/Ridge Nailer Board

• FBC does not explicitly require a nailer board, but **without