Florida, July.

Code Violations & Critical Errors (FBC 2023 / FBC-R):

1. Exposed Deck Overnight (FBC-R §R905.1.1 / §R903.1): Stripping 40 squares (4,000 SF) without same-day dry-in is a cardinal sin in Florida July. A 60% storm probability = near certainty of wind-driven rain. Synthetic underlayment is not a temporary roof; it requires capped fasteners (cap nails/staples) per FBC-R §R905.1.1(2) and manufacturer specs. If storms hit tonight, water enters the sheathing joints and nail holes.
2. No Re-Nailing Inspection/Documentation (FBC-R §R905.2.1 / §R703.1 / §R905.1.1): "Deck looks fine" is not code compliance. You must verify/renail sheathing to 8d ring-shank @ 6" edge / 12" field (or per engineered specs) for High Velocity Hurricane Zone (HVHZ) or FBC standard. No photos = no proof for permit final or insurance. If an inspector fails the deck nailing tomorrow, you strip the new underlayment.
3. Synthetic Underlayment Left Uncapped: Rolling out synthetic without capping fasteners (or button-caps) violates FBC-R §R905.1.1(2) and every major manufacturer (GAF, Owens Corning, Epilay). Wind will tear it off. It is not self-adhered.
4. No Temporary Dry-In Plan: No tarps, no roll roofing, no 30# felt staged. FBC §R903.1 requires the roof to resist water intrusion during construction.

Immediate Action Required (Tonight):

• Stop. Do not leave site.
• Install ASTM D226 Type II (#30 felt) or self-adhered membrane over the entire deck tonight using cap nails (12" o.c. max). This is your code-compliant temporary dry-in.
• Photograph every slope: sheathing nailing pattern, felt installation, flashings.
• Schedule re-nail inspection before synthetic goes down tomorrow.

Liability: If it rains tonight, you own the interior damage, mold remediation, and potential structural replacement. Florida Statute §553.84 (Contractor liability).

Several critical issues exist in this scenario:

1. Exposed Roof Deck: Leaving the roof deck uncovered overnight (or longer) violates Florida Building Code (FBC) §1507.1.1 and manufacturer requirements for most roofing systems. The deck is now vulnerable to rain, UV degradation, and wind uplift. Even if the deck "looks fine," moisture intrusion can cause rot, mold, or warping—especially in Florida’s humid climate.

1. No Weather Protection: With a 60% chance of afternoon storms, there’s significant risk of water intrusion. FBC §1507 requires weather protection during installation. Synthetic underlayment is a secondary barrier, but the primary defense is timely coverage. Delaying underlayment exposes the deck to potential leaks and long-term damage.

1. Lack of Documentation: No photos or re-nailing were done. FBC §1507.1.1 requires verification of deck condition before re-roofing. Without documentation, there’s no record of pre-existing damage or fastener integrity—critical for insurance claims or code compliance. Re-nailing may be required if fasteners are corroded or missing (per FBC §1507.1.1.1).

1. Scheduling Risk: Relying on delayed delivery without a weather contingency plan is poor practice. In Florida’s summer storm season, same-day underlayment installation is standard to avoid exposure.

Recommendation: Cover the deck immediately with a waterproof tarp (secured per FBC §1507.1.1) if underlayment can’t be installed today. Resume work only when materials arrive and weather permits. Document deck condition before re-covering. This is not a DIY fix—licensed roofing contractors should manage weather delays per FBC and OSHA safety standards. Do not proceed with shingles over a wet or damaged deck.