If you’ve ever caught a faint rotten egg smell in your home and felt your stomach drop, you already know the anxiety that comes with suspecting a gas leak. So – knowing what causes a gas leak is genuinely useful information – not just for peace of mind, but because understanding the source can help you spot the warning signs early before a small issue turns into an extremely dangerous one.
Because remember: Gas leaks don’t usually come out of nowhere. There’s almost always a reason – and more often than not, it’s something that could have been picked up sooner with a bit of awareness.
7 Common causes of gas leaks at home
So without further ado, here are the 7 most common causes of gas leaks in homes. Some of these you might expect, a couple might surprise you – but all of them are worth knowing.
Because when it comes to gas, the difference between catching something early and missing it can be the difference between a quick fix and a genuine emergency …
1. Old or corroded gas pipes
Pipes don’t last forever. Over time, metal gas lines can (and ultimately will):
- Corrode
- Weaken
- Develop small cracks or pinhole leaks.
Older homes in Brisbane are particularly susceptible if the original pipework has never been replaced or inspected. You may not see the damage from the outside – but a licensed gasfitter can identify deteriorating pipes before they become a problem.
2. Loose or damaged fittings & connections
Think of all the points where a gas line connects to an appliance at your place:
- Your stove
- Your hot water system
- Your heating unit.
All of them are potential weak points. Connections can loosen over time, or become damaged during renovations, moving appliances, or even just general wear. A fitting that’s slightly off is often all it takes.
3. Faulty or aging gas appliances
Gas pipes don’t last forever – and neither do appliances.
A gas stove, oven, or hot water unit that’s getting on in years can develop internal faults that lead to leaks at the burner or the valves and seals.
Regular servicing is the best way to catch these issues – and if your appliances are more than 10-15 years old, it’s worth having them properly assessed.
4. Poor installation
Not all gas work is created equal! An appliance or gas line that wasn’t installed correctly from the start may have connections that were never properly sealed – or fittings that weren’t suited to the job.
This is exactly why gas work must be carried out by a licensed gasfitter – it’s not just a legal requirement in Queensland, it’s a safety one.
5. Physical damage to gas lines
These ones catch homeowners off guard all the time:
- Digging in the garden
- Driving a stake into the ground
- Drilling into walls.
What they all have in common is that they can accidentally strike a gas line – alarmingly easily, too.
Ground movement and tree root intrusion can also shift or crack underground pipes over time. If you’re doing any work around your property, always check where your gas lines run first.
6. Earthquake or ground movement
Brisbane and surrounding areas don’t experience major seismic events often, but there are other things that can shift underground infrastructure too:
- Ground settling
- Soil movement
- Even prolonged dry or wet spells – and we have plenty of those!
Gas lines buried under concrete slabs or landscaping can be affected without any visible signs at ground level.
7. Lack of regular servicing
Understanding what causes a natural gas leak often comes down to one simple thing: neglect.
Gas systems that go years without inspection accumulate small issues that individually might seem minor – like a slightly loose fitting or worn seal or a bit of corrosion – but together create real risk.
Annual checks by a licensed gasfitter are the most straightforward way to stay ahead of it.
What to do if you suspect a gas leak
If you smell gas – that distinctive sulphur or rotten egg odour – or suspect a leak for any reason, treat it as an emergency and act immediately.
Knowing what causes a gas leak in a house is one thing – but the response is what matters most in the moment.
Here’s what to do:
Don’t touch switches or appliances: Even a single spark from a light switch or power point can ignite leaking gas – leave everything exactly as it is.
Step away from your phone: Don’t make or receive calls inside the building. Get outside first, then call for help.
Leave it to the professionals: Don’t go looking for the source or try to fix anything yourself. That’s what licensed gasfitters are for.
Open up on your way out: If it’s safe to do so, open doors and windows as you leave to help disperse the gas.
Get everyone out – including pets: Don’t wait to grab belongings. Get every person and animal out of the home immediately.
Don’t go back in: Stay out until emergency services or a licensed gasfitter has inspected the property and given the all-clear.
Call your gas supplier or 000: Once you’re outside and clear of the building, call triple zero for any immediate danger, or your gas distributor’s emergency line.
In Queensland, that’s Australian Gas Networks on 1800 427 532 (Brisbane Northside, Ipswich and beyond) or Allgas Energy on 1300 763 106 (Brisbane Southside, Gold Coast, Toowoomba). Not sure which one? Check your gas bill – the number will be on there.
If you’re unsure whether what you’re smelling is gas – always trust your instincts. It’s infinitely better to call and be wrong than to ignore it.
Understanding what causes a gas leak in house situations is useful background knowledge. But when you’re standing in your kitchen, and something smells off, none of that matters – just get out and call for help.
Think there’s a gas leak? Call S&J now
S&J Plumbing and Gasfitting are licensed gasfitters servicing Brisbane and surrounding areas 24/7. Whether it’s an emergency or you just want your gas system inspected, our team is ready to help – right now.