Joist hangars are made of what material and can compromise at what temperature?

• A. 18G Galvanized Steel at 800 Degrees
• B. 16G Aluminum at 700 Degrees
• C. 20G Stainless Steel at 900 Degrees
• D. 14G Copper at 600 Degrees

Answer: (A)

Joist hangers are typically made from 18-gauge galvanized steel, chosen for a balance of strength and corrosion resistance. The protective zinc coating on galvanized steel is what helps resist moisture, but it has a heat limit: zinc melts around 787°F, so as the temperature climbs toward about 800°F the coating can fail and the hanger’s protective performance is compromised. That makes 18-gauge galvanized steel at 800 degrees the best match for how these hardware items behave under fire or high-heat conditions. Other materials listed—aluminum, stainless steel, or copper with different gauges—are not standard choices for typical joist hangers, and their heat behavior wouldn’t align with the stated compromise temperature.