It is generally recommended to install the electrical distribution box before plastering so that it can be properly aligned and wired during the first-fix stage.

Timing and Positioning

Installing the distribution box before plastering allows the plasterer to finish the wall around the box, ensuring the front of the box sits flush with the final wall surface. Typically, the box should be mounted at the standard height of about 1.5 meters from the floor for residential installations, in a dry, accessible location with adequate ventilation . For industrial or outdoor setups, adjust the height and ensure proper waterproofing and protection according to IP or NEMA ratings .

Depth Considerations

When installing before plastering, you do not need to leave extra space for plaster thickness. The plasterer will apply the base coat and skim coat up to the front edge of the box, so the faceplate of switches or sockets will sit flush without requiring longer screws . If the plaster is particularly thick, confirm with the plasterer to avoid the box being recessed too deeply.

Coordination with Electricians and Plasterers

• First-fix wiring: The electrician should install the box and run all necessary cables before plastering begins .
• Plastering: The plasterer can mark the inside edges of the box while the plaster is wet to prevent plaster from filling the box and to ensure a clean finish .
• Protection: Consider using protective inserts or covers to prevent plaster from entering the box during wall finishing .

Safety and Compliance

Ensure the box is properly grounded, and all wiring follows local electrical codes. Use certified components and maintain clear space around the box for ventilation and future maintenance . Label circuits clearly and leave room for potential upgrades.

Summary

Installing the distribution box before plastering is the preferred method. It ensures proper alignment, allows first-fix wiring, and avoids the need to chase walls after plastering. Coordination with the plasterer and electrician is essential to achieve a flush, safe, and compliant installation.