I have worked on a number of jobs where insurance were involved or providing specs for several reasons.
An insurance spec for a thatched cottage rewire had to have:
Galv conduit in the walls and original Kopex [treated paper/ali/pvc layers] in the loft & contain only 1 circuit.
All cable stipulated as 2 sizes bigger than standard, ie 6mm for ring, 16mm cooker [2" Kopex] & 2.5mm lighting.
All circuits 2 pole MCB and separate RCD.
I did a fair bit of newbuild house bashing in the mid 70's and seeboard would not connect unless 'all exposed metal' was bonded and the b******s even tested door & window hinges and handles.
An insurance spec for a thatched cottage rewire had to have:
Galv conduit in the walls and original Kopex [treated paper/ali/pvc layers] in the loft & contain only 1 circuit.
All cable stipulated as 2 sizes bigger than standard, ie 6mm for ring, 16mm cooker [2" Kopex] & 2.5mm lighting.
All circuits 2 pole MCB and separate RCD.
I did a fair bit of newbuild house bashing in the mid 70's and seeboard would not connect unless 'all exposed metal' was bonded and the b******s even tested door & window hinges and handles.