House Smells Like Gas: What to Do Immediately

A suspected natural-gas or propane leak is an emergency condition and is not a DIY troubleshooting task.

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Before you startUse only the checks you can perform safely. Disconnect power before homeowner-serviceable cleaning or inspection. Stop when a repair involves gas, exposed wiring, high voltage, a roof, structural components, or anything outside your experience.

Common signs

Rotten-egg or sulfur-like odor
Hissing near gas equipment
Gas detector alarm

Most likely causes

1. Fuel-gas leak

A leak can occur at piping, valves, fittings, or appliances.

2. Appliance combustion problem

Malfunctioning fuel-burning equipment can be unsafe.

Safe checks to try first

Do not operate switches, phones, appliances, or flames inside the building.
Leave the building immediately and move to a safe location.
From outside and away from the building, contact the gas utility or emergency services.
Do not re-enter until authorities say it is safe.

When to call a professional

Only qualified gas/HVAC professionals should locate and repair the source after the emergency has been made safe.

Bottom line

Start with the simplest visible cause, change one thing at a time, and avoid repeated resets or disassembly when a safety device keeps tripping. A recurring problem usually deserves a proper diagnosis rather than a temporary workaround.