Coastal climate and exposure detailing · Lesson 4 of 4

Coastal climate and exposure detailing: defects, verification and case study

How to read a coastal defect, the common ones (rust at galvanized fasteners, sheltered undersides, copper run-off, edge lift), the safety boundary for inspection at height, a yearly inspection card, and a constructed case study.

You will be able to: Diagnose a plausible coastal corrosion defect from symptom to mechanism to evidence, explain corrective options as the designer's choice, and run the method on a constructed project.

10 min · 11 slides · 6 questions

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Slide 1 of 11

Reading a coastal defect

TB 8 suggests finding areas of higher corrosion by observing the state of corrosion of connectors and fasteners in older buildings at various distances from the shoreline.

A useful defect note has four parts: the symptom, the mechanism, the evidence and the options. The designer of record chooses the fix.

Sources

NFIP Technical Bulletin 8: Corrosion Protection for Metal Connectors and Fasteners in Coastal Areas (June 2019) - FEMA

Glossary

Mechanism: The reason a defect forms, such as salt accumulating on a surface rain does not reach. A defect note pairs the visible symptom with its mechanism, the evidence for it and the options to fix it.
Edge flashing blow-off: FEMA P-55 says roof membrane blow-off is typically caused by lifting and peeling of metal edge flashings (gravel stops) or copings, which clamp down the membrane at the roof edge.
Run-off staining: Damage to a metal surface from water that has run over another metal such as copper. The PAC-CLAD sample form excludes damage from run-off from lead, copper or other incompatible flashings.
Guardrail system: One of the fall protection systems OSHA lists in 1926.501(b) for work at 6 feet or more above lower levels, alongside safety net systems and personal fall arrest systems.