Symptoms and warning signs
How why has half my house lost power typically shows itself, and which signs mean the circuit should stay off until it has been inspected.
Likely electrical causes
- —Faulty or deteriorated protective device
- —Loose, damaged or overheating connection
- —Insulation breakdown or moisture ingress
- —Faulty appliance or equipment on the circuit
- —Overloaded circuit or supply-side problem
Immediate safety precautions
- —If you smell burning, see smoke or arcing — switch off at the main switch only if safe to do so
- —Do not touch anything wet, scorched or exposed
- —Do not repeatedly reset a tripping device
- —Do not open the consumer unit or distribution board
- —In a fire, leave the building and call 999
How our engineer diagnoses it
Safe isolation, visual inspection, then structured testing — insulation resistance, continuity, polarity, earth fault loop impedance and RCD tests as appropriate — to locate the fault rather than guess.
Typical repair options
- —Emergency isolation of the affected circuit
- —Temporary safe restoration of unaffected circuits
- —Permanent remedial repair with test results recorded
When urgent attendance is needed
Call immediately if there is smoke, a burning smell, heat at an accessory, water near electrics, a shock, or a loss of supply affecting vulnerable people or critical equipment.
Related services
Frequently asked questions
Is why has half my house lost power an emergency?
It is urgent if there is smoke, burning, heat, water near electrics, a shock, or loss of power to vulnerable people or critical equipment. If unsure, call us and we'll advise.
Can I fix it myself?
Resetting a device once is fine. Do not open consumer units or distribution boards, and never carry out live testing unless you are qualified.
Do you cover all of London?
Yes — we attend across Greater London, day and night.