What is an acceptable form of protection to allow a single-wall metal pipe vent connector installation with only 6 inches of clearance?

To achieve an acceptable form of protection for a single-wall metal pipe vent connector installation with only 6 inches of clearance, the correct choice involves using a combination of materials—specifically, a 1/2" insulation board over 1" glass fiber or mineral wool batts. This option is effective because it combines thermal resistance and structural stability, ensuring that the heat generated by the metal pipe does not exceed safe levels in the surrounding environment.

The 1/2" insulation board provides a robust thermal barrier, reducing the risk of heat transfer to combustible materials nearby. The glass fiber or mineral wool batts add additional insulation while also serving to mitigate any heat radiation coming from the metal vent connector. This multi-layered approach effectively enhances safety, preventing potential ignition of adjacent materials that could occur due to excessive heat.

In contrast, while insulation wrap and metal shielding offer some degree of heat protection, they may not meet the specific requirements for 6-inch clearance installations as thoroughly as the selected option. A concrete barrier, while very effective in some applications, can be overkill in many cases and may not be practical or necessary for vent connector installations. Thus, the combination of materials in the correct choice provides the ideal balance of safety, compliance with HVAC codes