How do I check my home is electrically safe?

Visual checks and test-button routines any householder can safely do, and the warning signs that need an electrician.

Difficulty: beginner
Time: 45 min
Read: 2 min
Safety: warning

Short answer

Test the RCD in your consumer unit every three months using its test button — it should trip instantly. Check for scorch marks, warm sockets and damaged cables, and never ignore a breaker that keeps tripping.

Almost all domestic electrical safety for a householder is inspection and testing built-in protection. The actual work belongs to a qualified electrician, but knowing what to look for and when to call is genuinely valuable.

Safety

Never attempt work inside a consumer unit, socket or fitting yourself unless qualified — mains electricity kills. Everything in this guide is visual inspection and testing of built-in safety features only. Any fault, burning smell, scorch mark or repeated tripping needs a qualified electrician immediately.

What you'll need

Torch
A clock or calendar reminder (optional)

Step by step

Find your consumer unit and know how to isolate the power.Everyone in the house should know where it is and which switch turns everything off. That matters in an emergency such as a leak.
Test the RCD every three months.Press the test button marked T. It should trip immediately. If it does not, call an electrician — that device is what protects against electric shock.
Look for scorch marks and discolouration.Around sockets, switches and plugs. Browning or a burnt smell indicates overheating and needs attention immediately.
Feel whether plugs or sockets are warm.A socket or plug that is warm in normal use is a fault. Unplug and stop using it until it is checked.
Check cables and leads for damage.Fraying, cuts, taped repairs, cables trapped under furniture or running under carpets. Replace rather than repair a damaged lead.
Check for overloaded sockets.Extension leads plugged into extension leads, or several high-power appliances on one adaptor. Heaters, kettles and washing machines are the ones that matter.
Note when the wiring was last inspected.A periodic inspection roughly every ten years for an owner-occupied home is the general guidance, and more often for rented property.
Never ignore repeated tripping.A breaker that trips repeatedly is detecting a genuine fault. Repeatedly resetting it is not a fix and is not safe.

Tips

Old rewireable fuse boxes with ceramic fuses and no RCD offer far less protection than modern units. Replacement is a worthwhile safety upgrade.
Plug-in RCD adaptors are a good precaution for garden tools and anything used outdoors, where the risk is highest.
Keep the consumer unit accessible and unobstructed. Being unable to reach it during an emergency is a real problem.

Common mistakes

Resetting a repeatedly tripping breaker — It is detecting a real fault — an overload, a short or an earth leak. Repeated resetting bypasses a safety device.
Running cables under carpets or rugs — They get crushed and abraded invisibly, and overheat with no way to notice until there is a fire.
Attempting work inside a consumer unit — There are live parts even with the main switch off in some units. This is qualified-electrician work without exception.

Questions people ask

How often should I test the RCD?

Every three months. Press the test button on the consumer unit; it should trip instantly. If it does not, the device protecting you from electric shock is not working and needs an electrician.

Why does my circuit breaker keep tripping?

It is detecting an overload, a short circuit or an earth fault. Unplug things on that circuit one at a time to identify a faulty appliance, and if it continues call an electrician rather than resetting repeatedly.