What Causes Flickering Lights (And When to Worry)

It’s a familiar sight for many Aussie homeowners—you turn on the light and it flickers for a moment. Sometimes it settles down, and sometimes it keeps flashing like you're at a disco. While an occasional flicker might seem harmless, it can also be a sign of a more serious electrical issue.

So, what causes flickering lights—and when should you worry?

1. Loose Light Bulbs or Fixtures

Sometimes the solution is simple. A bulb that’s not screwed in tightly or a loose connection in the fitting can cause intermittent contact, leading to flickering.

Quick fix: Turn off the power and check if the bulb is screwed in properly. If it’s an LED, try replacing it—cheap or incompatible LEDs can flicker.

2. Faulty Light Switches

If the flicker happens when you toggle a switch, the issue might lie there. Worn-out or poorly installed switches can cause brief disruptions in the circuit.

 Pro tip: If the switch feels loose, clicks oddly, or causes a buzzing sound, it should be replaced by a licensed electrician.

3. Voltage Fluctuations

Major appliances (like air conditioners, fridges, or washing machines) draw a large current when they cycle on. If lights flicker when appliances start up, you may have a voltage fluctuation issue.

This can be a sign of a more serious problem—especially if:

• Multiple lights dim or flicker simultaneously

• Lights brighten unexpectedly

• Appliances seem to be underperforming

4. Overloaded Circuits

Too many devices plugged into one circuit can overload it, causing flickering or dimming lights. This is common in older homes not designed for today’s high-power usage.

5. Old or Faulty Wiring

If your home is more than 30 years old and the flickering is widespread, the cause might be aged, degraded, or improperly installed wiring.

Old wiring (such as VIR or cotton-insulated cable) becomes brittle over time and poses a fire risk. It may also become a serious fire and electric shock danger.

Warning signs to watch for:

• Flickering across multiple rooms

• Buzzing sounds behind walls

• Burning smells near power points

• Discoloured light switches or sockets

6. Loose or Corroded Connections in the Switchboard

If you’ve ruled out bulbs and switches, the flicker may be happening at your switchboard. Loose neutral connections are particularly dangerous—they can cause lights to flicker, appliances to fail, or even lead to electrical fires.

This is not a DIY fix. All electrical including switchboard work must be done by a licensed electrician under Australian law.

When to Worry

You should contact a licensed electrician if:

• The flickering is frequent or getting worse

• It's happening in multiple areas of your home

• It's accompanied by a burning smell or buzzing noise

• Lights dim when appliances are turned on

• Your switchboard hasn’t been upgraded in decades

What You Can Do

1. Try the simple checks first – Change the bulb or test a different lamp

2. Don’t ignore ongoing flickers – They’re often a warning sign.

3. Book an electrical safety inspection – Especially in older homes.

4. Upgrade your switchboard – Modern boards with RCDs (safety switches) are now required for new circuits in homes under AS/NZS 3000.

5. Avoid DIY electrical work – It’s illegal and dangerous in Australia.

Need a professional opinion? Reach out to your local sparkie and ask about an electrical safety check today.