This study uses a metal stud partition fireproof drywall measuring 83 mm in thickness as a test specimen to explore the impact of an embedded junction box on the firefighting performance of the wall through one time of standard fire test on a 300 cm × 300 cm area and five times of standard fire test on a 120 cm × 120 cm area. The results show that the quality of calcium silicate board plays a big role in the fireproof effectiveness. The embedded junction box located on the backside of the fire can reduce the effectiveness of the wall, especially the area above the socket. The thickness of rock wool may increase the performance, but in a limited rate. External junction box may not impact the fireproofing performance of the wall but it still possesses some safety risks. An embedded junction box measuring 101 × 55 mm could already damage the fire compartment, and in reality there may be more complicated situations that should be noted and improved.

e metallic-framework drywall is used as the specimens in this research. e standard fire test and finite element simulation were performed once on 300 cm × 300 cm area specimen and twice on 100 cm × 100 cm area specimens, to quantify and evaluate the effect of the junction boxes on the fireproof property after being embedded into the metallic-framework drywall. e results of the experiment show that the temperature of unexposed surface rises faster due to the higher thermal conductivity of the internal metal junction box. e general junction box whose material is PVC can be softened off when heated, affecting the integrity of the firewall and also leading to rapid transfer to the unexposed surface. e prediction of finite element simulation temperature is highly correlated with the results of the real experiment. It is effective to strengthen the original weaknesses by adding a calcium silicate board behind the junction box and using metal panels instead of PVC. e temperature of the temperature junction box surface which is the highest temperature point of unexposed surface decreased most significantly at 72.9°C after the reinforcement. In addition, after reinforcement, the fire resistance time can reach to 1 hour by inserting the junction box into the metallicframework drywall.

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