Fire-resistant electrical junction boxes and method of manufacture

摘要

An electrical junction box has an interior electrical component container having a forward opening, and a second rearwardly opening container portion which opens rearwardly and is filled with insulating material. The housing is a one-piece unit preferably molded from fire- resistant fiberglass. The junction box is manufactured by molding a one- piece fiberglass housing, filling the rearwardly opening chamber with a fluid insulating material such as calcinated gypsum, allowing the insulating material to harden, and drilling a hole from the exterior of the unit into the interior chamber to permit wiring or conduits to extend to the box.