Installing and Using Gas Heating and Appliances in France

Find out about gas piping, ventilation, the fitters' qualifications, Certificates of Conformity and other French gas regulations...

Strict regulations apply to gas installations in France. These regulations are intended to ensure that properties with gas are safe. Over 300 people die in France each year as a result of incidents relating to gas installations, mainly due to carbon monoxide poisoning.

The following information is a general summary as gas installation procedures will vary according to circumstances.

Gas Regulations

The following aspects of installation of gas supplies and appliances are regulated:

  • Pipe installations - permitted materials for the installation of supply pipework, valves, fittings, solders and the manner in which they can be installed
  • Location of appliances - where it is permissible to locate a gas appliance within a property
  • Ventilation - what is required to provide fresh air and to extract exhaust
  • Evacuation of combustion products (exhaust) - installation of flues, chimneys and the requirements for removal of exhaust
  • Testing - permitted methods and required pressures when fitting a gas appliance

The regulations are diverse and may be interpreted differently for each specific installation depending on location or equipment (there may be a different requirement for the same appliance when installed in two different locations).

Note that electrical regulations must also be taken into consideration when installing equipment.

Gas Products

Natural gas is available in the majority of towns in France, but as much of France is rural, GPL (butane and propane) is also very common. Other gases, such as Gaz de Lacq, air propane and air butane are available but they are relatively uncommon. These are the most commonly used gas products:

  • Natural gas: Supply pressure 20mbar; lighter than air; piped directly to properties
  • Propane: Supply pressure 37mbar from bottle, 1.5bar from storage tank, reducing to 37mbar at appliance; heavier than air; pressures inside bottles and tanks are much higher; stored in above-ground or buried tanks outdoors or supplied loose in bottles. The maximum size of bottle allowed inside a building is 6.5 litres (2.8 Kg)
  • Butane: Supply pressure 28mbar; heavier than air; supplied in bottles only and for interior use only, the maximum size of bottle allowed inside a building is 10 litres (13 Kg)

Bottled gas is stored in liquid form and should only ever used in a vertical position. When using propane, it is recommended to locate the bottle outside if possible. Single bottles are permitted inside dwellings, but twin bottle installations must be kept outside.

Professional Installers

As well as passing an exam every three years to retain their certificate, registered installers must provide annual proof of company details and evidence of public liability and decennial insurance (assurance décennale). They are subject to annual audit by Qualigaz and suffer penalties for even a minor non-conformance in installation.

When a registered installer inspects a property, they are legally obliged to check existing gas installations, and is required to advise the customer of any aspect that is not in compliance with the regulations. The registered installer has no authority to enforce any remedial work, which is the responsibility of the building owner. Registered installers have a legal obligation to comply with gas regulations and may face criminal charges in the event of death or injury following an incident involving a gas appliance.

The gas distributor is responsible for control of the gas main up to the meter or the propane tank. The installation professional is responsible for installation from the meter or tank to and within a property and will normally be required to issue the appropriate certificate.

Certificates of Conformity

A Certificate of Conformity (Certificat de Conformité) should be obtained after a gas-appliance installation, though this does not apply to single bottle installations with flexible tube connections to a single appliance such as a cooker, some water heaters and direct replacement of valves and flexible tubes.

All certificates must be sent to Qualigaz (the controlling body) to be approved and stamped. This must be done before the gas distributor will turn on a gas supply.

Qualigaz-registered professionals have authority to issue certificates. Non-registered professionals can carry out installations but must pay a fee for a site inspection by a Qualigaz-certified technician who will only issue a certificate if they are satisfied regulations have been followed.

Gas Diagnostic Certificate

A Gas Diagnostic Certificate (Un état de l'installation intérieure de gaz naturel), which is different from a Certificate of Conformity, must be produced when selling a property. The Gas Diagnostic Certificate is an inspection report of a property's gas system and lists any items not in compliance with regulations. When selling a home, the certificate must be less than one year old.

Categories of Gas Appliances

All gas appliances are covered by the regulations. They fall in to three categories:

  1. Flued and aspirated appliance (Appareils à circuit étanche): These are balanced-flue or ventouse gas boilers and heaters with a twin wall flue, products of combustion exiting via the central tube and fresh air being drawn in within the outer wall. They are safer than other types of gas appliances and therefore greater flexibility is allowed in installation.
  2. Flued appliances (Appareils à circuit non étanche raccordés): These are conventionally-flued gas boilers and water heaters. These may be naturally aspirated or fitted with a fan to assist evacuation of the exhaust gases. Restrictions apply to the location of the appliances, the volume of the space in which they are installed, air supply and air exhaust from the area.
  3. Un-flued appliance (Appareils non raccordés): These are gas appliances without flues. Combustion gases are released into the space where the appliance is located. They include mainly cookers and geyser-type water heaters.

The regulations are strict in regard to installation of these appliances in order to ensure proper ventilation of the area to prevent a dangerous build-up of carbon monoxide. For example, if installing a water heater of this type it can only be placed in the kitchen or an annex such as a laundry room. If it is installed in a kitchen it must be at the centre of the main wall, the kitchen must have a minimum volume and ventilation needs to be installed. All these heaters must have safety equipment incorporated; a water heater cannot be connected to a shower or a bath. It is recommended not to install un-flued appliances, other than gas cookers, in a property.


The purpose of ventilation is to:

  • Provide air for combustion (low-level vent)
  • Provide air to remove products of combustion (high-level vent)
  • Facilitate the rapid evacuation of gas or fumes (open window)

Ventilation requirements depend on the appliance and the safety equipment installed. In modern properties a VMC (Ventilation Mécanique Contrôlée) system is normally used to ventilate the property. This consists of an extract fan located in the roof that draws air from the kitchen and bathroom. Fresh air is drawn in through vents normally located in living and bedroom areas at the top of windows. A constant supply of fresh air is drawn throughout the property. The air flow provides the correct level of ventilation for gas appliances. It is very important that the VMC unit is allowed to operate continuously.

Older properties are generally fitted with high and low level ducted vents that draw air in from the outside to the room with the gas appliance.

Kitchen extract hoods

It is recommended to obtain professional advice when installing a fan-assisted extract hood in a kitchen that has a gas boiler or water heater as extract fans that do not recycle the air can reduce air pressure in the kitchen. If a gas appliance is naturally ventilated (there is no fan on the boiler flue) this can result in the exhaust being drawn in to the kitchen. This kind of configuration is banned in France.

Evacuation of the products of combustion

Regulations apply to materials and methods for installation of flue pipes and use of chimneys. These restrictions apply to many factors, including the materials that can be used, the number and angles of bends, types of joint, inclusion of tees to give access for cleaning, usage of existing chimneys, point of discharge and what type of liners are permissible.

Pipe Installations

Gas pipe installations are strictly controlled. Where and how gas pipework is used is clearly defined as are allowed materials, fittings, methods of jointing, types of solder, placement of joints and pipe proximity to other services.

Flexible Tubing

When installing a gas cooker, only a single flexible tube with a maximum length of two metres may be used. Joining two flexible tubes together is not permitted.

Flexible tubes must have threaded connections factory-fitted, the use of jubilee clips and other methods of jointing is prohibited. It is recommended to use a flexible metallic tube, either with an expiry date of 10 years or preferably with no expiry date. Avoid using rubber flexible tubing with a five year expiry date as the use of these is restricted. Expiration dates are clearly marked on tubing. Expired flexible tubes should be replaced promptly.


Testing of gas installations should be undertaken by a professional. If a small leak is suspected around a fitting, brush on a soap solution. If a leak is present, bubbles will emerge. If a gas leak is suspected, call the gas company immediately.


The purpose of the regulations is to ensure safe installation and operation of gas equipment. Carbon monoxide can be lethal and undetectable:

  • 0.1% concentration in air will kill in 1 hour
  • 1% concentration in air will kill in 10 minutes
  • 10% concentration in air will kill immediately

Gas explosions are also a hazard:

  • 4% concentration in air is enough for an explosive mixture for natural gas
  • 2% concentration in air is enough for an explosive mixture for propane gas