The weights, per square metre
| Type | Cabinet weight | With steel frame |
|---|---|---|
| Indoor P2.5 die-cast | 7 – 9 kg/m² | 16 – 20 kg/m² |
| Indoor P1.5 die-cast | 9 – 11 kg/m² | 19 – 24 kg/m² |
| Outdoor P4 steel | 22 – 28 kg/m² | 34 – 42 kg/m² |
| Outdoor P8 steel | 28 – 34 kg/m² | 40 – 50 kg/m² |
Why the frame dominates
A 20 square metre indoor wall at 8 kg/m² is 160 kg of cabinets. The steel to hold it rigidly, keep it flat, and allow service access is often 200 to 250 kg. People budget for the screen and forget the steel, then discover the wall cannot take the combined load.
The three fixing questions
- What is behind the plaster? Concrete, block, metal stud, or drywall on studs?
- How thick is the slab, and can you drill 80 mm deep without hitting post-tension cable?
- Is there a beam at the top of the wall, or are you hanging from a ceiling grid?
The load is not just vertical
An outdoor wall in a windy location sees horizontal load. A 30 square metre screen at 1.2 kN/m² wind pressure is 36 kN pushing sideways, which is more demanding than its own weight. Indoor walls rarely see this, but a wall mounted in a loading dock or an open atrium can.
What to give the engineer
Wall dimensions, total weight, fixing pattern, distance from the wall to the centre of mass, and the wind or seismic assumption. One page. Engineers are fast when the inputs are clear, and slow when they have to guess.
A note on existing buildings
In retrofit work, the wall is often the strongest thing in the room. Concrete or block is easy. The expensive case is a glass curtain wall, where you end up building a freestanding steel frame that transfers load to the floor. Budget for that before you promise a flush finish.