The B3’s 1-3/8” depth sets it apart from standard outlet boxes, and that extra quarter-inch makes all the difference when you’re trying to stuff a dimmer switch into a surface-mount raceway. Heavy-duty steel construction means it’ll outlast the building—this isn’t flimsy residential-grade tin.
Deep Box for Demanding Devices
At 1-3/8 inches (1.375 in) depth, the B3 solves a real problem. Standard surface-mount boxes can’t handle modern dimmers, fan speed controls, or smart switches with their bulky electronics. The deep dimension accommodates larger devices like dimmers and speed-control switches that would otherwise require wall surgery or compromise on device selection.
Heavy-duty steel construction handles commercial abuse. The corrosion-resistant baked enamel finish comes in standard ivory or white (BW3 version). The white BW3 variant is paintable to match décor—though most contractors stick with the ivory that matches existing Wiremold systems.
| Specification | Value |
|---|---|
| Depth | 1-3/8 inches (1.375 in) |
| Material | Steel |
| Finish Options | Ivory baked enamel (standard), White (BW3 version) |
| Mounting Style | Surface-mount |
| Compatibility | B1 Raceway system, 500/700 Series Metal Raceway |
| Certification | UL Listed |
Installation Reality
The B3 adapts an existing outlet as the starting point of a wiring system. Surface-mounted directly to the wall or B1 raceway, it transforms a flush outlet into the beginning of a surface raceway run. Designed to be secured to the raceway and then wired in-place—no gymnastics required.
The deep cavity handles oversized devices (dimmers, speed-control switches, etc.) that cause headaches in shallow boxes. Think Lutron Maestro dimmers, Leviton fan controllers, or any smart switch with a hefty electronics package. Montana’s older commercial buildings and ranch properties benefit from this approach—you’re adding modern controls without opening walls.
The B1 Outlet Box serves as the shallower alternative when device depth isn’t an issue. But when you need the room, the B3 delivers without forcing compromises on device selection.
Common Questions
What devices specifically need the B3’s extra depth? Dimmers and speed-control switches are the primary drivers. Most modern dimmers with heat sinks, smart switches with wireless modules, and fan speed controls need that extra half-inch the B3 provides over standard boxes.
Is the B3 paintable to match walls? The white BW3 variant is specifically paintable. The standard ivory finish takes paint poorly—order the BW3 if color matching matters.
How does this mount to existing wiring? It adapts an existing outlet as the starting point, surface-mounting directly to the wall or B1 raceway. No wall demolition required.
What’s the difference between B3 and other Wiremold boxes? The B3 is the ‘deep-outlet’ version (1-3/8” depth) compared to the shallower B1 box. BW3 is the white, paintable version of the B3.
Frequently Asked Questions
Q: What’s the actual depth of the Wiremold B3 box and why does it matter?
The Wiremold B3 measures 1-3/8 inches (1.375”) deep, specifically designed to accommodate larger devices like dimmers and speed-control switches that won’t fit in standard shallow boxes. That extra depth compared to the standard B1 box means you can install modern dimmers with heat sinks or smart switches without cramming components.
Q: Is the Wiremold B3 paintable to match wall color?
The standard Wiremold B3 comes in ivory baked enamel finish, but the BW3 variant is specifically designed to be paintable in white. If color matching matters for your installation, order the BW3 version rather than trying to paint the standard ivory model.
Q: What raceway systems is the B3 compatible with?
The Wiremold B3 works with the B1 Raceway system and is compatible with both 500 Series and 700 Series Metal Raceway systems. It’s designed to adapt an existing outlet as the starting point for a surface-mounted wiring system.
Q: Is the Wiremold B3 approved for commercial installations?
Yes, the Wiremold B3 is UL Listed and features heavy-duty steel construction with corrosion-resistant baked enamel finish suitable for commercial use. The surface-mount design is ideal for adding switches or outlets to existing commercial spaces without opening walls.
Q: What’s the difference between the Wiremold B3 and B1 outlet boxes?
The Wiremold B3 is the deep-outlet version at 1-3/8” depth, while the B1 is a shallower box for standard devices. Choose the B3 when installing dimmers, fan speed controls, or other devices with bulky electronics that need extra room.
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