Skip to main content

Corrosion


On a roof with copper flashing secured by galvanized steel nails, which metal will corrode the more anodic metal over time as the roof is exposed to rain water?

A. copper flashing
B. galvanized nails
C. neither, the metals are not dissimilar
D. both will equally corrode in contact

AnswerA. copper flashing, more noble and cathodic, will corrode the galvanized nails as electrolytic rainwater is introduced. Contact between 2 metals at different ends of the galvanic scale should be avoided, or non-conductive coatings or materials could separate them.
ARE 4.0 exam prep: BDCS

Resource tip: Read about galvanic action at archtoolbox.com

Comments

Try These Too!

Risk management

How does an owner provide a financial safeguard for the following situations: - unanticipated price escalation of a particular product - an architect’s omission of flashing in the construction documents - a necessary change during construction, modifying the project’s scope. A. Allowance B. Alternates C. Contingency D. Escalation Answer C. Contingency is an amount, usually a percentage, that is part of the project budget to offset changes in the scope of the project, unknown conditions, and gaps/oversights in the documents. ARE 4.0 exam prep: PPP

Fire detection

Which of the following detector types can detect smoke or a smoldering fire that has not yet burst into flames? A. Ionization B. Rise-of-temperature C. Photoelectric D. Flame detectors