29mm Single Back Box - White

Description

Description
The Knightsbridge 29mm single back box is a surface-mounted PVC containment unit for single-gang switches and sockets. The white moulded housing measures 86.3mm square with a 32.2mm projection from the wall, providing 29mm of recessed depth for cable terminations and the back of the faceplate mechanism.

Built from high-impact PVC rather than metal, the box can be drilled or cut without cracking, which is useful when running additional cable entries mid-installation or adapting the box for non-standard trunking routes. Pre-moulded square and circular knockouts on the top, bottom and centre allow conduit or trunking to enter from multiple directions without needing to modify the box body.

Designed for surface installation in residential, office and light commercial settings, the 29mm recessed depth accommodates standard single-pole or DP switches, 13A sockets and dimmer modules without forcing cable bunching behind the mechanism. The white finish blends with painted plasterboard or white dado trunking runs. The IP20 rating limits use to dry indoor locations away from water ingress.

Specification

Height
86.3mm

Width
86.3mm

Depth
32.2mm

Projection
32.2mm

Recessed Depth
29mm

Construction
PVC

Finish
White

IP Rating
IP20

Warranty
25 Year Guarantee

Downloads
Product Specification Sheet

Frequently Asked
What's the difference between recessed depth and projection?

Recessed depth (29mm) is the internal space available for cable terminations and the back of the switch or socket mechanism. Projection (32.2mm) is the total distance the box stands out from the wall surface, including the PVC wall thickness.

Can this be used with screwless faceplates?

Yes, but screwless faceplates typically require a separate metal sub-frame that fixes to the back box using lugs. Check that the sub-frame you're using is compatible with standard 86.3mm single-gang back boxes.

What faceplates fit this back box?

Any standard UK single-gang switch, socket or dimmer faceplate with the 86.3mm mounting centres will fit. This includes Knightsbridge, MK, Varilight, BG Electrical and other brands using the UK standard fixing spacing.

Is the 29mm depth enough for USB sockets?

Most single-gang USB sockets need 35mm minimum back box depth to accommodate the USB charging module behind the faceplate. For USB sockets, use a deeper back box (35mm or 47mm) to avoid forcing cables and to allow the faceplate to sit flush.