Andrew wrote:

He says part 18

IET 18th edition?

will require all properties that are within 1 Km of a church or tower
block with lightning rods,

Not heard the "within 1km of a church" wording anywhere else, sounds
like bollox

will need to be fitted with surge protection devices.

In any case, SPDs don't apply to single dwellings

https://the-regs.co.uk/blog/?p=492