Surge Protection — Whole House SPD Guide

A consumer-unit Surge Protection Device protects everything in your home from voltage spikes — for less than the cost of one new TV.

Why a Type 2 SPD is the modern standard

Since BS 7671 18th Edition Amendment 2 (2022), surge protection is required in most new installs unless a documented risk assessment shows otherwise. Modern homes contain £10,000+ of sensitive electronics — a £180 SPD is cheap insurance.

What an SPD protects you from

  • Nearby lightning strikes (transient overvoltage carried in via the grid)
  • Grid switching events from the DNO
  • Large motor turn-off spikes (your own or a neighbour's)
  • EV charger contactor switching
  • Damage to TVs, computers, smart-home hubs, fridges, boilers and LED drivers

Get whole-house surge protection fitted

From £180 plus VAT. Same-week appointments. Devon-wide. CHAS approved.

Frequently Asked Questions

What is a surge protector and do I need one?

A Surge Protection Device (SPD) is fitted in your consumer unit and clamps voltage spikes to a safe level — typically caused by lightning strikes, the grid switching or large motors turning off. Since the 18th Edition Amendment 2 (2022), an SPD is required in most new domestic installations and we strongly recommend retrofitting one to any property with electronics, EV chargers or solar.

Are whole-house surge protectors worth it?

Yes. Plug-in extension surge strips only protect what is plugged into them. A consumer-unit-mounted Type 2 SPD protects every appliance in the house — TVs, computers, fridges, smart-home gear, EV chargers — from a single £180 plus VAT install.

How much does a surge protector cost to install?

A Type 2 SPD installed into your existing consumer unit is typically £180–£240 plus VAT depending on space and brand. If your consumer unit is full or older than 2008, an upgrade may be the cleaner option — full RCBO + SPD board from £750 plus VAT.

Will a surge protector stop a lightning strike?

A direct strike, no — nothing will. But the vast majority of "lightning damage" is actually transient overvoltage from a strike up to a mile away, conducted in via the grid. A properly installed Type 2 SPD diverts that surge to earth before it reaches your appliances.

Where should the SPD go?

In the consumer unit, on the supply side of the main RCDs/RCBOs, with the shortest possible earth lead (under 0.5m ideally). Done correctly it protects every circuit; done badly it does very little. We follow the manufacturer wiring diagram exactly and certify the install.