Description
Single Black Cavity Box: Flush Mounting for Hollow Walls
A Single Black Cavity Box is specifically engineered for “new work” or retrofit installations where there is no solid wall behind the mounting surface . Unlike surface-mounted pattress boxes that sit proud of the wall, this cavity box is inserted into a pre-cut hole, allowing the socket or switch to sit flush with the wall for a seamless appearance .
Commonly referred to as an adaptor box, it is the standard solution for mounting electrical accessories in stud partitions, plasterboard linings, and other hollow constructions. The box is inserted into the wall cavity and secured using integrated lugs or clamps that tighten against the rear face of the wallboard .
Single Black Cavity Box: Key Specifications
| Specification | Details |
|---|---|
| Type | Single gang cavity wall box / adaptor box |
| Colour | Black |
| Material | Thermoplastic resin / Plastic |
| Mounting | Flush (recessed into wall cavity) |
| Wall Compatibility | Plasterboard, drywall, wood panelling, gypsum board |
| Hole Diameter | Typically 68mm – 73mm |
| Features | Adjustable clamping lugs, cable knockouts |
| Certification | UL Listed (varies by manufacturer) |
Single Black Cavity Box: Design and Construction
Manufactured from high-quality thermoplastic, this cavity box offers excellent durability and electrical insulation properties. The black colouration is particularly useful in modern installations where the box may be visible behind accessories with cut-out sections, or where an all-black aesthetic is desired for industrial and contemporary design schemes.
The box features pre-scored knockouts on multiple sides to accommodate cable entry from various directions. These can be easily removed to create clean openings for electrical cables without the need for special tools . The design ensures that wiring can be routed neatly and safely within the wall cavity.
Single Black Cavity Box: Installation Features
Installation of this single cavity box is straightforward, making it a favourite among electricians for both new builds and renovations:
Precise Fit: Requires a correctly sized hole (typically 68-73mm) drilled using a hole saw or cut using a plasterboard saw .
Adjustable Clamps: Features rotating lugs or clamping mechanisms that tighten against the back of the wallboard as the fixing screws are turned. This secures the box firmly in place without damaging the front surface .
Depth Compatibility: Suitable for various wall thicknesses, typically accommodating boards from 1/4″ to 1-1/2″ (approx. 6mm to 38mm) .
Gangable: Many single boxes can be linked together side-by-side to create multiple-gang configurations for larger switch plates or multiple sockets .
Single Black Cavity Box: Applications
This versatile adaptor box is used in a wide range of settings where cavity walls are present:
Residential Installations: Mounting sockets and switches in plasterboard partitions, stud walls, and dry-lined rooms.
Commercial Fit-Outs: Installing electrical accessories in office partitions, retail displays, and modular wall systems.
Renovation Projects: Adding new sockets to existing plasterboard walls without chasing into masonry.
Timber-Framed Construction: Providing secure mounting points in timber-panelled interiors.
Industrial-Style Interiors: The black finish complements exposed conduit, black sockets, and raw material aesthetics.
Single Black Cavity Box: Compatibility
This single-gang box is designed to accept standard UK and European pattern socket outlets, switches, and data outlets. The fixing holes align with the standard 60.3mm centres used by most wiring accessory manufacturers. When paired with black sockets and switches, the box remains discreetly hidden while contributing to a cohesive, professional finish.
Single Black Cavity Box: Quality and Compliance
Quality cavity boxes are manufactured to meet rigorous safety and performance standards. Look for certifications such as UL listing or compliance with relevant British/European standards, ensuring the product has been tested for fire resistance, mechanical strength, and electrical safety .
When installed correctly by a qualified electrician, the Single Black Cavity Box provides a secure, long-lasting foundation for electrical accessories in any cavity wall construction, combining practical functionality with an aesthetic suited to modern design trends.
