Metal - clad buildings and the confused forum member.

A bit of light reading:


7. EARTHING

7.1 Separate Services Originating outside the Building

7.1.1 Where services are to be installed in accordance with subsection 5.2 in low-rise domestic and commercial (retail or offices) premises of conventional construction (brick, stone, concrete), interconnection of the neutral cores of the separate services, either within the building or through the fabric of the building, is unlikely. PME connections, via CNE service cables, shall normally be used.

7.1.2 In steel-framed or steel-clad buildings (eg industrial units), interconnection of the neutral cores of separate service cables, through the fabric of the building, shall be avoided. Where it is not practicable to establish a single Intake Position, with an incoming PME connection and internal SNE sub-services provided by the Landlord, BNO or Customers, the service connections to the separate units shall be SNE. These may be derived directly from the LV Network or via a feeder pillar, with an incoming CNE connection.

7.1.3 Where Premises in a steel-framed or metal-clad building with an existing CNE connection are to be divided into separate Premises and where it is not practicable to establish a single Intake Position, the existing service shall be disconnected and removed and each of the newly divided Premises connected externally, using SNE cables. Any other existing CNE connections in the same building, not affected by the division of Premises, may remain as they are, unless problems caused by the diversion of neutral currents are reported.

https://www.enwl.co.uk/globalassets/get-connected/cic/icpsidnos/g81-library/1---design--planning/5-design--planning/es287---connections-to-multi-occupancy-buildings.pdf


That is the recommendation, however implementation may vary.


Andy Betteridge

A bit of light reading:


7. EARTHING

7.1 Separate Services Originating outside the Building

7.1.1 Where services are to be installed in accordance with subsection 5.2 in low-rise domestic and commercial (retail or offices) premises of conventional construction (brick, stone, concrete), interconnection of the neutral cores of the separate services, either within the building or through the fabric of the building, is unlikely. PME connections, via CNE service cables, shall normally be used.

7.1.2 In steel-framed or steel-clad buildings (eg industrial units), interconnection of the neutral cores of separate service cables, through the fabric of the building, shall be avoided. Where it is not practicable to establish a single Intake Position, with an incoming PME connection and internal SNE sub-services provided by the Landlord, BNO or Customers, the service connections to the separate units shall be SNE. These may be derived directly from the LV Network or via a feeder pillar, with an incoming CNE connection.

7.1.3 Where Premises in a steel-framed or metal-clad building with an existing CNE connection are to be divided into separate Premises and where it is not practicable to establish a single Intake Position, the existing service shall be disconnected and removed and each of the newly divided Premises connected externally, using SNE cables. Any other existing CNE connections in the same building, not affected by the division of Premises, may remain as they are, unless problems caused by the diversion of neutral currents are reported.

https://www.enwl.co.uk/globalassets/get-connected/cic/icpsidnos/g81-library/1---design--planning/5-design--planning/es287---connections-to-multi-occupancy-buildings.pdf


That is the recommendation, however implementation may vary.


Andy Betteridge