Non-metallic Boxes FAQ -Allied Moulded Products

1. Why are more contractors using non-metallic electrical boxes?

Residential electrical contractors prefer non-metallic electric boxes because they are aesthetically pleasing for surface mount applications and are faster to install because they don’t require grounding.

Industrial facility contractors use fiberglass or polycarbonate electrical boxes because they perform extremely well when compared to metal boxes in the following:

• Chemical resistant
• Anti-corrosive (salt, water)
• Anti-static and insulating
• Suitable for hose-down environments
• UV light tolerant
• Withstands organic solvents

2. Can you field modify non-metallic boxes?

Non-metallic electrical boxes have pre-cut knock-outs that are easily removed with a screwdriver and there are adjustable plastic boxes that will easily fit different wall thicknesses with a simple turn of a screw.

Many non-metallic electrical boxes have integral cable clamps for use with nonmetallic conduit systems and nonmetallic sheath cabling to reduce field work.

3. Which industries benefit from plastic electrical enclosures?

Most all industries and outdoor applications will benefit from plastic electrical enclosures, but they are particularly suited for the following:

• Solar Energy
• Residential Electrical
• Telecommunications
• Chemical facilities
• Food and Beverage
• Manufacturing
• Marine and Coastal
• Oil Refineries

4. When to choose fiberglass electrical boxes?

Fiberglass electrical boxes are more aesthetically-appealing and feature thermal insulating properties, so they are often preferred for high-end residential construction.

The mechanical properties of fiberglass make these electrical boxes immune to radio frequency and EMI interference and have sound absorbing properties, making them preferred for specialty applications like solar power generation.

5. Can non-metallic boxes be installed in fire-rated assemblies?

Non-metallic outlet boxes can be used in specific fire-rated ceilings, floor/ceiling or roof/ceiling assemblies, and in wall and partition assemblies in accordance with the National Electrical Code (NEC).

*They must be classified by the manufacturer as Outlet Boxes and Fittings Classified for Fire Resistance (QBWY), in the UL Electrical Construction Equipment Directory, and under CEYY in Volume 1 of the UL Fire Resistance Directory.

*Metallic and Non-metallic Outlet Boxes Used in Fire-rated Assembly