A pattress box, also known as a back box, is a housing unit installed in walls or ceilings to hold electrical outlets, switches, or other electrical fixtures. It provides support and protection for the wiring and electrical components.

Pattress boxes come in various sizes to accommodate different electrical fittings:

• Single gang: Typically 86mm x 86mm.
• Double gang: Typically 146mm x 86mm.
• Depths: Common depths include 16mm, 25mm, 35mm, and 47mm.

Plastic pattress boxes are typically used for dry lining or plasterboard walls. For solid walls like brick or concrete, metal pattress boxes are preferred due to their durability and fire resistance.

Yes, metal pattress boxes must be earthed to ensure electrical safety. They typically have an earth terminal for this purpose. Plastic boxes do not require earthing.

Flush-Mounted Pattress Boxes: Installed within the wall, flush with the surface, providing a cleaner look.

Surface-Mounted Pattress Boxes: Mounted on the wall surface, used when recessing the box into the wall is not feasible.