The Wiremold B3 Deep Outlet Box solves a specific problem that standard boxes can’t touch — dimmers and speed-control switches that need 1-3/8 inches of depth to fit properly. Most surface-mount boxes skimp on depth to stay flush against the wall. Wiremold went the opposite direction with their CM raceway system, building boxes deep enough to handle oversized devices without cramming.
Heavy-Duty Steel Construction That Handles Montana Weather
The B3 box features heavy-duty steel construction with a corrosion-resistant baked enamel finish. That steel body matters when you’re mounting on exterior walls or unheated garages where temperature swings from -30°F to 90°F put stress on materials. Plastic raceways crack in cold weather. This steel construction takes the abuse.
The B3 model comes standard in ivory baked enamel finish, while the BW3 variant offers white paintable finish. The white BW3 version can be painted to match décor — though most contractors stick with the standard ivory that hides minor scuffs better.
| Specification | Value |
|---|---|
| Depth | 1-3/8 inches (1.375 in) |
| Material | Steel |
| Standard Finish | Ivory baked enamel |
| White Version | BW3 model |
| Mounting Style | Surface-mount |
| Series Compatibility | 500 / 700 Series Metal Raceway |
| Certification | UL listed |
Compatible Systems and Real-World Applications
The B3 box works with Wiremold’s B1 Raceway system and both 500 and 700 Series Metal Raceway lines. It adapts an existing outlet as the starting point of a wiring system, surface-mounting directly to the wall or B1 raceway. This matters for retrofit work — you’re not tearing into walls to add circuits.
Common applications include installing dimmers and speed-control switches, surface mounting electrical wiring or communication cables, extending an existing outlet into a surface-mounted wiring system, and residential and commercial wiring projects requiring extra depth.
The deep dimension shines in older Montana buildings where you’re adding modern dimmers to knob-and-tube or early Romex circuits. Those old systems never anticipated the bulk of today’s smart switches and motor controls. Surface mounting with proper depth beats cramming devices into shallow boxes that overheat.
Compared to the standard Wiremold B1 Outlet Box, the B3 is specifically the ‘deep-outlet’ version with its 1-3/8” depth versus the shallower B1 box. That extra depth isn’t luxury — it’s necessary clearance for heat dissipation on dimmers and the mechanical components in speed controls.
Frequently Asked Questions
Q: What makes the B3 different from standard surface-mount boxes?
The B3 provides 1-3/8 inches of depth specifically to accommodate larger devices like dimmers and speed-control switches, compared to standard surface-mount boxes that prioritize minimal wall projection.
Q: Can the ivory finish be painted?
The standard ivory B3 has a baked enamel finish that’s not designed for painting. For paintable options, choose the white BW3 variant which can be painted to match décor.
Q: What raceway systems work with the B3 box?
The B3 box is compatible with Wiremold’s B1 Raceway system, 500 Series Metal Raceway, and 700 Series Metal Raceway.
Q: Is this box suitable for outdoor installation?
While the B3 features corrosion-resistant baked enamel finish on heavy-duty steel construction, it’s designed for surface-mount applications on interior walls, garages, and protected exterior locations. Full weather exposure requires additional protection.
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