Underfloor systems

Floor structure height and free space for device use

The minimum floor structure height for the installation of device installation units is primarily dependent on the connector types and sizes used. The required free space is calculated from the dimension between the underside of the lid and the top edge of the universal support.

The universal support can be installed at various heights in the locking ladder of the device installation units. The appropriate free space can be created for this.

If the universal socket has been mounted in the top usable level of the locking ladder, then free space of at least 24 mm is available. This distance is sufficient for the angular connector dimensions, but not, however, for power connectors, straight connectors and USB charging devices. The connector structure heights must be determined for the calculation of the necessary free space.

Installation of multimedia technology
The free space for the installation of data and multimedia technology cannot be clearly determined on account of the many different connector types, sizes and shapes. It must be determined after the connection solution and the connectors have been specified.

Determination of the required free space
The dimensions of the connectors used must be known for the determination of the free space. The minimum free space for use can be calculated using the appropriate corrective measures for the connector types.

Connector height (H) + corrective dimension (K) = minimum free space for use

Protective contact angle connector (H) 35 mm + corrective dimension (K) 12.5 mm = 22.5 mm free space when connector is used

Socket types

Correction dimension (K)

Protective contact

–12.5 mm

With earthing pin

–9.5 mm

British Standard

+5.5 mm

South Africa

+5.5 mm


+5.5 mm


+5.5 mm


+5.5 mm


–8.5 mm


–8.5 mm