What Causes a Gas Leak?

Gas leaks are one of those household problems that you simply can't afford to ignore. Not only are they a major safety hazard, but even a small leak can quickly escalate into a serious emergency.

But what actually causes a gas leak in the first place? The truth is, there are several potential reasons – and many of them are preventable with the right care and attention. From ageing appliances and corroded pipes to accidental damage during home renovations, gas leaks can happen when you least expect them.

Understanding the common causes is the first step toward keeping your home and family safe. In this article, we’ll break down the most frequent reasons gas leaks occur and what you can do to reduce the risk

Faulty or Ageing Gas Appliances

Over time, even the best gas appliances – from ducted gas heating and gas log fires to gas stoves – can wear out and become a source of leaks. Regular maintenance is key, but sometimes age or unnoticed faults can cause problems.

Here’s how ageing appliances can lead to gas leaks:

• Worn seals and connections – Gaskets, hoses and fittings can degrade, leading to small but dangerous leaks.
• Rust and corrosion – Moisture and long-term use can cause metal parts to corrode, weakening the structure of the appliance.
• Internal component failure – Parts like valves or burners may fail after years of use, allowing gas to escape unexpectedly.
• Poor ventilation – Older appliances may no longer vent gas properly, increasing the risk of leaks inside your home.

If your gas appliances are more than 10 years old, it’s a good idea to have them inspected regularly by a licensed technician to catch any issues early.

Poorly Installed Gas Lines

When gas lines aren’t installed properly, it creates a hidden danger that can put your entire home at risk. Poor workmanship, using the wrong materials, or skipping important safety checks can all lead to serious gas leaks over time.

Even small mistakes, like loose fittings or incorrect pipe connections, can allow gas to slowly seep out and build up in enclosed spaces.

This is why it’s so important to only trust licensed, experienced professionals when installing or upgrading gas lines. Qualified technicians follow strict regulations, use certified materials, and test for leaks before finishing the job.

If your gas lines were installed by an unlicensed person, or if you’ve recently moved into a home with unknown history, it’s smart to arrange an inspection.

Spotting and fixing poor installation early can prevent dangerous leaks, save you money on repairs, and most importantly, keep your family safe.

Damaged or Corroded Gas Pipes

Gas pipes are built to last, but over time they can suffer damage from various sources. When pipes weaken, cracks or holes can develop, leading to dangerous gas leaks.

Here are some common causes of pipe damage and corrosion:

• Age and wear – Like anything else, gas pipes naturally degrade after decades of use, especially if they’re made from older materials like steel.
• Exposure to moisture – Underground or outdoor pipes exposed to rain, soil moisture, or flooding are more likely to rust and corrode.
• Ground movement – Shifting soil from construction, erosion, or earthquakes can stress or crack gas lines.
• Accidental impact – Digging in the yard or heavy machinery work can damage underground gas pipes without you even knowing.

If your home is older or you’ve noticed unusual smells or sounds, it’s worth having a licensed professional inspect your gas lines.

Accidental Damage During Renovations

Home renovations are exciting, but they can also come with hidden risks – including accidental damage to gas lines.

When walls are knocked down, floors are ripped up or trenches are dug outside, it’s easy to unknowingly hit a gas pipe. Even a small dent or crack can weaken the line and cause a slow leak that might not be noticed right away.

Before starting any major work, it’s important to know exactly where your gas lines are located. Always consult building plans, or better yet, hire a licensed professional to locate and mark them.

If you’re planning drilling, digging, or heavy construction, taking these extra steps could save you from a dangerous situation later on. And if you accidentally strike a gas line during a project, stop work immediately and call a qualified gas technician to inspect and repair the damage safely.

Faulty Gas Fittings or Valves

Gas fittings and valves play a crucial role in keeping your system sealed and safe. But when these parts become faulty, they can slowly leak gas without you even noticing.

Here are a few ways fittings and valves can cause problems:

• Wear and tear – Over time, seals, threads, and joints can degrade, leading to small but dangerous leaks.
• Improper installation – If fittings aren’t tightened correctly or valves aren’t sealed properly, gaps can allow gas to escape.
• Low-quality parts – Cheap or non-certified fittings may not meet safety standards and are more likely to fail.
• Lack of maintenance – Regular inspections can catch loose or aging valves before they turn into a serious hazard.

If you suspect a fitting or valve problem, don’t try to fix it yourself – call a licensed gas fitter to check and repair it safely.

Natural Disasters and External Forces

Sometimes, gas leaks aren’t caused by anything you did – they’re the result of powerful natural forces.

Events like earthquakes, floods, severe storms or even major ground movement can shift, crack or rupture gas pipes. Underground lines are especially vulnerable because they can be damaged without any obvious signs at the surface.

Tree roots are another surprising culprit. As roots grow, they can push against buried gas lines, eventually causing them to bend, crack or break.

After any major weather event or noticeable ground shift, it’s a smart idea to have your gas system professionally inspected, even if you don’t notice an immediate problem.

Small cracks or weaknesses can worsen over time. Being proactive could help you catch a potential leak early, keeping your home safe and avoiding costly emergency repairs down the track.

Manufacturing Defects

While gas leaks are often blamed on wear and tear or poor installation, sometimes the issue starts right at the source – with a manufacturing defect.

Even brand-new gas appliances, pipes, valves, or fittings can have hidden flaws that aren’t noticeable at first. Tiny cracks, weak seals, or faulty components can slowly develop into leaks over time as the product is used.

That’s why it’s so important to buy appliances and parts from trusted brands and ensure they meet strict Australian safety standards. Certified products go through rigorous testing to minimise the risk of defects.

Even with quality items, things can slip through the cracks. If you’ve recently installed a new gas appliance and notice odd smells, noises, or performance issues, don’t ignore them.

Getting a professional to check it early could prevent a minor fault from turning into a dangerous gas leak later on.

Warning Signs of a Gas Leak

Gas leaks aren’t always easy to spot, but knowing the warning signs can help you act quickly and stay safe. Here’s what to watch out for:

• Smell of rotten eggs – Natural gas is treated with a chemical that smells like sulphur or rotten eggs to alert you to leaks.
• Hissing or whistling sounds – A gas leak can sometimes produce a faint hissing noise near pipes or appliances.
• Dead or dying plants – If plants near gas lines suddenly wither without explanation, it could indicate a leak underground.
• Visible damage to gas lines – Cracks, corrosion or loose connections are physical signs that shouldn’t be ignored.
• Headaches or dizziness indoors – Exposure to leaking gas can cause health symptoms like headaches, nausea or light-headedness.

If you notice any of these signs, evacuate immediately and call emergency services.

What to Do If You Suspect a Gas Leak

If you think there’s a gas leak in your home, acting quickly and safely is essential. Here’s what you should do:

1. Turn off the gas supply – If it’s safe to do so, shut off the main gas valve to stop the flow.
2. Leave the area immediately – Get everyone out of the house or affected area without delay.
3. Avoid using electrical devices – Don’t switch lights on or off, use phones, or anything that might create a spark.
4. Do not light matches or flames – Even a small spark can ignite leaking gas.
5. Call emergency services – Once safely outside, call your gas provider or emergency services to report the leak.
6. Arrange a professional inspection – A licensed gas fitter should check your system before you return.

Always prioritise safety – it’s better to be cautious when dealing with gas leaks.

Protect Your Home and Family

Gas leaks are a serious safety concern, but understanding what causes them can go a long way in helping you prevent one.

From ageing appliances and damaged pipes to poor installation and even natural disasters, there are many reasons a leak can occur. The good news is that with regular maintenance, professional inspections and a little extra care during renovations, many gas leaks can be avoided altogether.

Always keep an eye out for warning signs like strange smells, hissing sounds or dying plants. And remember, if you ever suspect a leak, act quickly – your safety comes first. By staying informed and proactive, you can protect your home, your family and your peace of mind.

Please note: This information is provided for advice purposes only. Regulations differ from state to state, so please consult your local authorities or an industry professional before proceeding with any work. See our Terms & Conditions here.