Lights flicker for one of three reasons, and how much of the house is affected tells you which one you have: a bulb, LED driver or dimmer at the end of its life in a single fitting; a loose connection in the fixed wiring shared by several lights; or a dip in the supply coming into the property, which belongs to the electricity network operator rather than to you. The first you can settle yourself in five minutes. The second is the one that matters, because a loose connection gets hot. It is one of the calls we take most often from Nottingham homes. Fault finding on a flickering circuit is work for a registered electrician — nothing below asks you to open a consumer unit, socket or light fitting. Why do my lights flicker, and what does the pattern tell you? Flickering is an erratic flutter in brightness; dimming is a brief drop when something heavy switches on. The useful question is not what the light is doing, but how much of the house is doing it. • One fitting only. Almost always the bulb, its LED driver, or a dimmer never designed for the lamp now in it. • Several lights on one circuit, together. Points at the fixed wiring they share — most often a loose terminal in a switch, ceiling rose, junction box or downlight connector. This is the version to take seriously. • The whole house, briefly, when an appliance starts. A shower, oven or tumble dryer drawing a large current can cause a visible dip. Slight and occasional is ordinary in older housing stock; pronounced, or every single time, is worth having looked at. • The whole house at random, or the whole street. Usually the incoming supply or the network outside, not your installation. Which flickering is urgent, and which can wait? Urgency is set by what else you can see, smell and feel, not by how annoying the flicker is. How urgent What you are seeing What to do Someone out today A burning or fishy smell, scorching or browning round a switch, socket or fitting, buzzing or crackling, anything warm that should not be, a shock or tingle from metalwork, or flicker that began after water got in Switch that circuit off, stop using it, call an electrician the same day. If you can see smoke, call 999 first Book it in this week Several lights flickering together, flicker that is getting worse or spreading, flicker with no appliance running, or a dip every time one appliance starts Normal appointment. Note when it happens beforehand — it shortens the job Deal with it yourself One fitting only, no smell, nothing warm, no marks, rest of the house steady Try a different bulb, and check it suits the dimmer In the first row, the lights still working is not reassurance: a connection that arcs intermittently produces heat inside a sealed fitting while still working. What can I safely check first? None of these involves touching any wiring. Work down the list, and stop at step 6. • Switch that light off, let it cool, and fit a different bulb you know is good. A lamp not quite making contact in its holder, or near the end of its life, is the commonest cause. • Check the bulb and dimmer are a matched pair. The lamp must be marked dimmable and the dimmer intended for LEDs. A mismatch flickers and buzzes. • Work out how far it spreads. Turn the other lights on and watch. One room, one floor, or everywhere? • Watch what else is running. Does it coincide with the shower, oven or washing machine starting, and every time? • Ask a neighbour. If the houses either side do the same thing, the problem is outside your property. • Stop there. If a different bulb has not fixed it, the next step is testing the fixed wiring — opening switches, roses and the consumer unit, on circuits that may be live. That is not a householder job, and it is the point to call a registered electrician. What not to do: do not take the cover off the consumer unit, do not unscrew a switch or socket front, do not tighten a terminal, and do not keep resetting a breaker that trips alongside the flicker. Is it my house or the whole street? If several nearby homes flicker or dim at the same moment, the cause is almost certainly the distribution network in the street, and no work inside the house will fix it. Report it to your local electricity network operator — the company that owns the cables and the substation, not the supplier you pay. The free national power cut line, 105, routes you to the right operator for your postcode. Keep a log of dates and times first: network faults are often intermittent, and a pattern is what lets them find it. If it is only your property, it is your installation, and the age of the wiring matters. Much of the terraced and inter-war housing around Long Eaton still has lighting circuits with original junction boxes buried out of reach — exactly where a termination works loose over decades of heating and cooling. What will an electrician do about flickering lights? Fault finding is a diagnostic visit rather than a fixed job, so it is normally charged by time. The usual order: confirm which circuit the symptom is on, test continuity and insulation resistance on it, then inspect the terminations along it until the loose or damaged one is found. Often the repair is one termination remade, and the visit is short. Where the problem is the condition of the circuit rather than one point — brittle insulation, damaged cable, no earth at the switches — the next step is usually an electrical installation condition report , an EICR, which assesses the whole installation and says whether this is a repair or a rewire. Our guides to the signs a fuse board needs replacing and a new consumer unit or a full rewire cover that decision. Whoever you call, check they are registered with a competent person scheme first. NAPIT's find-an-installer search and the Electrical Safety First register both check a registration number for you. Frequently asked questions Are flickering lights dangerous? One fitting flickering on a tired bulb is not. Several lights flickering together usually means a loose connection in the fixed wiring, which is a genuine fire risk: current arcs across the gap and produces heat. Flickering with a burning smell, scorch marks, buzzing or anything warm is urgent — switch that circuit off. Why do my lights flicker when I turn on an appliance? Because the appliance briefly draws a large current and the voltage across the rest of the installation dips while it does. A slight, occasional dip when a shower or oven starts is normal. A pronounced dip, or one every time, can point to an overloaded circuit or a poor connection, and is worth testing. Can an LED bulb cause flickering? Yes, and it is one of the commonest causes. LED lamps draw very little current, so a dimmer or switch designed for filament bulbs may not run them steadily. Fitting a lamp marked dimmable, with a dimmer intended for LEDs, usually settles it. A failing LED driver inside the fitting flickers too. Do flickering lights mean I need rewiring? Not on their own. Most flickering traces back to one bulb, one dimmer or one loose termination, and the repair is small. Rewiring becomes the question only when testing shows the circuit is at the end of its life — brittle insulation, no earth at the lighting points, or faults in several places. Electrical fault finding with Somo Electrical Somo Electrical is a NAPIT-registered electrical contractor, registration number 33320, working across Nottingham and the surrounding area including Long Eaton . We trace intermittent faults, repair what we find, and say plainly when a circuit needs more than a repair — or when the answer is a different bulb. Call 07733 666004 for an emergency electrical repair , or use our online quote form to book a visit. Fault finding is charged by time, because nobody can say how long a fault takes to find before looking at it — our guide to what an electrician charges per hour in Nottingham explains how. If a breaker or RCD is tripping too, start with why an RCD keeps tripping . Written 9 October 2026. This article states no price and makes no claim about any regulation or legal duty — it describes causes, symptoms and process only. The warning signs above are general electrical practice, not a reading of any standard, and no primary source could be opened from the environment it was drafted in, so nothing here states what a standard or regulation requires. The power cut number 105 is taken from published UK guidance and was not verified against a primary source this run. NAPIT registration 33320 is confirmed by the business. Diagnosing and repairing a fault in fixed wiring is work for a qualified, registered electrician.