Spds - multiple consumer units

[mainline]

In my opinion if you have distribution boards downstream a reasonable distance from the other distribution boards then these really should have their own SPD as well. One at the origin won't cut it.

When a sub-distribution board is located more than 10m away from the mains SPD, additional SPDs are required.
Both his consumer units are close together.
It leaves the question of does the garage need one.

 

[tidytech]

Could someone kindly share why the SPD unit must be in parallel? I'm confused sorry! Hard to say without a basic wiring diagram of the current installation.
I assume a plastic 100A isolator switch with a built in SPD would work straight after the main supply incoming tails. Then anything downstream will be protected, including the time delayed RCD and all the other CCUs. . Though not strictly allowed (dno only), but could be placed in the meter cabinet. Here are examples:

Wylex type 2 SPD isolator, suitable for TT


There may already be an isolator after the main tails not sure. But that could be replaced with this.