fiberglassBOX™: Fire Resistive Ratings

Wall Ceiling Box AD

To the electrical contractor, wall space is at a premium. Allied Moulded's fiberglass reinforced polyester (FRP) electrical boxes give you the freedom to make the most of your space, with an exclusive industry fire rating, backed by UL® testing, that bucks the installation limitations found in 2-HR fire resistive walls. Our fiberglassBOX™ series of FRP wall boxes—up to and including three-gangs—can be safely mounted in opposing walls within a mere three inches of each other in all U300 wall configurations. Their PVC and metal counterparts can't get closer than two feet of each other without additional protection and cost! Plus, these FRP boxes require no additional fire protection, like putty pads, mineral wool or insulations, whose costs in both materials and labor can really add up, especially in multi-family homes. And since multiple boxes are placed in a single cavity, you can significantly reduce the amount of nonmetallic sheathed cable required—saving you even more time and money.

Frequently Asked Questions
CEYY.R9379 Outlet Boxes and Fittings Classified for Fire Resistance



Fire Resistive Wall & Ceiling Ratings

Wall Boxes  - VideoFire Wall

Nonmetallic outlet and switch boxes with various suffixes for use in 1 and 2 hr fire rated
gypsum board/wood stud wall assemblies framed with min 3-1/2 in. wide wood studs and constructed as specified in the individual U300 Series Wall and Partition Designs in the Fire Resistance Directory. Clearance between boxes and cut-outs in wall shall not exceed 1/8 in. The area of openings for boxes shall not aggregate more than 100 sq in. per 100 sq ft of wall or partition area with no opening exceeding 22.0 sq in. Outlet and switch boxes on opposite sides of a wall or partition within the same stud cavity shall be separated by a horizontal distance of not less than 3 in. Boxes are suitable for installation in staggered stud wall configuration. Outlet and switch boxes on opposite sides of the wall and in separate stud cavities may be separated by a horizontal spacing of not less than 1-1/2 in.

Ceiling Boxes - videoFire Ceiling

Nonmetallic outlet boxes with various suffixes, intended for fixture supports. For use in fire
resistance floor-ceiling assemblies consisting of wood floor, solid or pre-engineered wood joists or trusses and gypsum board ceiling with Classification periods of 2 hrs or less. Clearance between boxes and cutouts in ceiling shall not exceed 1/8 in. The area of openings for boxes shall not aggregate more than 64.7 sq in. per 100 sq ft of ceiling area, with no opening exceeding 12.5 sq in. No box shall be located within 4.5 ft of another box within a common joist cavity. When the supports are solid wood joists or pre-engineered wood joists with solid web members, the distance between boxes in adjacent cavities may be reduced to 5-1/2 in. center-to-center.


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