Dossier ENGIE
Abnormal gas consumption: possible causes and what to do
Is your gas bill unusually high and your gas consumption has suddenly increased compared to your last reading? Discover how to identify the cause of the issue and what solutions are available to you.
In a home, gas is used in many ways: for heating, cooking meals, or taking a hot shower. It can therefore represent a significant share of a household’s energy budget. In 2019, network gas accounted for nearly a quarter of energy expenses for French households on average. To avoid unpleasant surprises, it is essential to understand what influences your gas consumption so you can better anticipate and monitor your spending.
Mon Pilotage Gaz : équilibrez température et budget
What are the common causes of excessive gas consumption?
Weather and climate factors
Contrary to what you might think, weather is the main factor influencing a home’s annual gas consumption. While gas prices constantly evolving remain important, most of your energy bill depends on the region where you live and the weather conditions. As you can imagine, households in mountainous areas consume more gas for heating than those living on the Mediterranean coast. Insulation also plays a key role in annual gas consumption related to heating and climate. Insulating your roof, walls, and floors is one of the most effective eco-actions to reduce your gas bill.
A leak in your gas installation
Even a small gas leak can impact your consumption and your bills. Not to mention that it represents a safety risk for you, other occupants, and your equipment.
If you smell gas, there is no doubt: your system is affected by a leak. However, if the leak is not detectable by smell, a sudden increase in your gas consumption—and especially its impact on your bill may alert you. Other signs can confirm the presence of a leak: a gas detector alarm, unusual noises, or even specific physical symptoms.
In any case, at the slightest doubt, try to identify the source of the leak. If it is significant, immediately open doors and windows, turn off your gas supply, leave your home without touching electrical devices, alert your neighbours, and contact specialised professionals.
Ageing gas appliances
Did you know that older gas appliances tend to consume more energy? This is often observed with equipment such as water heaters, which can become particularly energy-intensive over time. An outdated boiler can also cause excessive consumption. Similarly, a poorly maintained, clogged, or improperly adjusted boiler tends to overconsume.
Remember that annual boiler maintenance is mandatory for the occupant of the property (owner or tenant).
Poor insulation in your home
As mentioned earlier, insulation plays a major role in your gas consumption. If it is inadequate, heat loss can be significant. As soon as temperatures drop, or during particularly cold winters, your gas bills are likely to increase sharply.
Energy-intensive habits
Your daily habits and consumption behaviour naturally have a major impact on your overall energy use.
For example, ADEME estimates that increasing the temperature in your home by just 1°C leads to a 7% increase in your energy bill.
Changes in the number of occupants and time spent at home
Living alone, as a couple, or with children also affects your gas consumption: the more people in your household, the more hot water you use and the more cooking is required. For instance, the arrival of a baby can significantly increase gas consumption, especially as you may heat the baby’s room more.
Similarly, the more time you spend at home, the more continuous heating you need. If you work from home several days a week, your gas bill is likely to reflect this increase.
To keep control of your gas consumption in larger households, consider connected devices such as the Mon Pilotage Gaz service, which allows everyone to manage heating precisely via mobile devices.
Could abnormal consumption be due to fraud?
Although rare, you could be the victim of a fraudulent connection to your meter. In such cases, your consumption will show an abnormal pattern. If you suspect fraud, contact the dedicated service of GRDF. Available 24/7, it can be reached at 0 800 47 33 33 (free call from a landline in France).
How can you identify the causes of abnormal gas consumption?
While it is easy to detect a major gas leak thanks to its smell, identifying a minor leak or another cause of abnormal consumption can be more complex. However, several strategies can help you detect it.
First, monitor your meter readings regularly. You can do this by checking your gas bills. You can also find this information via your online services (customer account, the M@ Relève service that allows you to submit your meter readings, online invoices, etc.). You can also discuss your consumption with customer advisors.
Another method is to compare your current consumption with your historical data. How? By regularly taking your own gas meter readings. If you have a Gazpar smart meter, you can access these readings directly from your online customer area.
How to take a self-reading easily
To take a self-reading, first identify the index. It corresponds to the first five digits before the decimal point, displayed on a black background. Then record it at regular intervals (days/weeks/months) and subtract the first value from the last: you will obtain an estimate of your gas consumption in cubic meters (m³).
To convert this consumption into kWh, you must apply a conversion coefficient.
Finally, it is important to understand and anticipate your gas consumption to detect anomalies more easily. If you find it difficult to estimate your consumption throughout the year, note that with a Gazpar meter, you can access all your data from your online customer account. You will know how much you have consumed so far, whether you had guests, went on holiday, or experienced a particularly cold winter followed by milder weather. You can also compare your consumption with similar households.
Also note that with ENGIE’s alert service, you are notified if your consumption exceeds expectations.
What solutions can help reduce peaks in gas consumption?
Depending on the cause of your abnormal gas consumption, the solutions will vary. Here is an overview.
Replace energy-intensive appliances with efficient models
Unlike older equipment, newer gas appliances are designed to optimise consumption. By choosing energy-efficient models (class A or higher), you can achieve significant energy savings. Installing a high-performance boiler can reduce your energy consumption by up to 20%.
However, even the best equipment can overconsume if it is poorly maintained or incorrectly adjusted. Do not neglect annual maintenance, which is also a legal requirement. This can help you save up to 12% of energy.
Improve your home’s thermal insulation
To sustainably reduce your energy expenses and control your heating bills, proper insulation is essential. A well-insulated roof can save up to 30% of energy. At the same time, well-insulated windows can reduce your home’s energy consumption by up to 15%.
Adopt new consumption habits
By adopting eco-friendly habits in your daily life, you can achieve up to 40% savings in gas consumption.
Avoid overconsumption related to heating
As we have seen, replacing your boiler with a high-performance (THPE) model is one solution. But other actions can also help:
Heat rooms according to ADEME recommendations: 19°C in living areas and 16°C in bedrooms.
Turn off radiators when airing your home.
Close shutters at night to reduce heat loss.
Install a room thermostat for better temperature control in winter.
Program heating schedules based on your presence and absence to optimise energy use. Consider remote heating control solutions.
For the last two points, you can rely on ENGIE’s Mon Pilotage Gaz solution. Developed in partnership with Netatmo, it allows you to precisely control your gas heating and reduce your consumption.
What eco-friendly habits in the kitchen can help limit abnormal gas consumption?
To limit rising consumption, simple habits can also be applied in the kitchen.
Regularly clean your gas stove burners: when the flame is yellow and irregular, they may be clogged and need cleaning. Also remember to cover your pots: this can divide cooking energy consumption by up to four. Make sure your cookware matches the size of your burners, if it is too small, energy is wasted.
Finally, turn off the gas supply when leaving for an extended period. This prevents unnecessary consumption and improves safety in your home, especially during summer.
Abnormal gas consumption: key takeaways
When your gas meter spins faster and your bills rise, it is natural to want to identify the cause.
Your first step should be to look at weather conditions, then check for a possible leak. Ageing or poorly maintained appliances, insufficient insulation, an increase in occupants, or more time spent at home are also common causes. More rarely, a meter malfunction or fraud may explain abnormal consumption.
To identify and anticipate anomalies, carefully review your bills. If you have a Gazpar meter, regularly check your customer account to monitor your consumption day by day. If you still have an older meter, do not hesitate to take manual readings.
To return to reasonable gas consumption levels, several solutions are available: replace outdated equipment, improve insulation, and adopt eco-friendly habits. Easy to implement, these actions can reduce your gas consumption by up to 40%.
What are the signs of abnormal gas overconsumption in a home?
The main warning sign is an unusually high gas bill without any change in your lifestyle. Other signs include difficulty reaching the desired temperature in your rooms or frequent start/stop cycles of your boiler.
How can I check if my high gas bill is due to actual overconsumption or an estimate?
With a Gazpar meter, actual consumption is always measured but not always billed immediately. You may be billed based on an estimated annual consumption spread over the year. In this case, an increase in your bill may result from an upward revision of your estimated consumption. Your supplier is required to inform you. This helps avoid a large adjustment bill on your contract anniversary. All consumption remains payable, but payments are spread over time.
How can I monitor my gas meter to detect abnormal consumption?
Use an elimination test: turn off all gas-powered appliances (boiler, stove, water heater if separate). Wait 15 minutes, then check your meter index. If it has changed, there may be residual consumption or a potential leak.
What are the most common causes of heating-related gas overconsumption?
The main causes are often behavioural: incorrect thermostat settings or lack of proper scheduling during the day or night. They may also be linked to a malfunction or a gas leak. The latter is particularly dangerous—any smell of gas should alert you immediately.
How can I detect a leak or malfunction in my gas installation?
If you notice a strong sulphur smell (added to gas for detection), immediately shut off the gas supply and call emergency services. If your boiler shows signs of malfunction (unstable flame, yellow instead of blue, or soot), it indicates incomplete combustion and requires a heating engineer to improve safety and performance.
Can a poorly adjusted or faulty boiler cause gas overconsumption?
Yes, this is a common cause. If your boiler is not serviced annually, it becomes clogged and loses efficiency. Worn parts or incorrect burner settings can also force it to consume more gas to maintain the same heat, leading to significant overconsumption.
What insulation issues can lead to increased gas consumption?
Poor insulation causes major heat loss. To compensate, your boiler runs more frequently and at higher intensity, directly increasing your gas consumption.
Can domestic hot water (DHW) cause gas overconsumption?
Absolutely. If the DHW temperature is set unnecessarily high (above 55°C except in specific cases), it consumes more gas. Likewise, even a small hot water leak (such as a dripping tap) forces the boiler to reheat water continuously.
What solutions exist to sustainably reduce gas overconsumption?
The most effective solution is regular boiler maintenance. Next, invest in a programmable thermostat to better manage temperature. In the long term, improving your home’s insulation is the most effective way to sustainably reduce heating demand.
Does ENGIE offer support to understand gas overconsumption?
ENGIE helps you consume less and better by offering several tools, options, and services. Customers of more than one year, for example, can book an appointment with a specialised energy advisor. This service is called “Mon Rendez-vous ENGIE”, a personalized consultation to help you optimize your energy consumption.
