Is my boiler's location now against building regs?

The combi boiler in our maison secondaire is about 15 years old. When it was serviced in August we discussed replacement, but the plumber was very concerned about using the current location. It’s on a rear outside wall and the flue opens into a lean-to structure with a corrugated metal roof and half open sides - it’s absolutely not airtight, and was there when the boiler was first fitted. Moving it would involve a big change within the kitchen, not to mention drilling through a 2 feet thick wall, so we would really prefer to use the current location.

Does anyone know how I can find out whether building regs have changed?

Start at your local mairie, they can point you in the right direction. Things have changed greatly since I was involved in building stuff and finding out the correct normes etc for OH.

If it’s the same as UK it might be illegal now but if it was fitted when it was legal it’s still okay. It will just have to be changed if it is renewed. Good luck.

crikey, that takes me back 45 years or so!
We had a balanced flue gas boiler fitted with the flue opening out under a corrugated cement fibre car port roof which connected our property to our neighbours and provided us both with cover for our respective cars.
What a nightmare!
It was our first house and so we were young and inexperienced in these matters but the fallout from this dreadful episode still lingers on!
Other than getting sued by the building firm who fitted it because we didn’t pay them following complaints from our neighbour about the stains on their car from the drips we eventually managed to settle out of court and sold the property having learnt a number of life lessons.
By the time the flue was sorted, we had already moved and I can’t now recall how it was finally resolved but it wasn’t a pleasant experience for us.
We were told that it was an extremely dangerous practice and the firm, although registered CORGI installers were entirely in the wrong but, as they say, two wrongs don’t make a right so we ended up paying for their mistake.
I realise this was years ago and in the UK (not France) but I do think that the regulations concerning flue outlets follow a similar pattern so I would take appropriate advice before proceeding further.


D’un point de vue réglementaire (Réglementation DTU 61.1 P4), le conduit de raccordement et la ventouse doivent respecter des instructions précises en termes de fabrication puis en termes d’installation. Concernant la pose, l’interdiction de toute contre-pente fait partie des prérequis pour garantir la bonne évacuation des fumées provoquées par la combustion. Afin de rendre plus simple l’écoulement des condensats, les normes en vigueur recommandent en outre l’existence d’une pente d’environ 3% .

Toute ouverture (fenêtre, porte d’entrée…) doit se trouver à plus de 40 centimètres du débouché de la ventouse (évacuation extérieure des fumées), qui doit elle-même se situer à 60 centimètres de toute ventilation. Ce débouché doit également être positionné à 1,80m de hauteur par rapport au sol. Quant au débouché en toiture, il doit se trouver à 30 centimètres au-dessus de toute surface horizontale.

Can the flue be extended through the roof of the structure? Manufacturers installation instructions would have to comply with all regs.


Thanks to everyone for your kind replies, with apologies for not acknowledging them sooner. For some reason I’m not getting the usual notifications.

I will translate the regs helpfully posted by JaneJones and have a chat with the Mairie when we next visit. Extending the flue upwards would definitely be the least disruptive option…hopefully we won’t be in a Graham-like nightmare situation as we have nothing worth dripping on!

by email or from your icon on the title bar (or neither)?

There are plenty of options off the shelf for sealing flashings around flues and lots of other penetrations.

Neither - I used to get email notifications but they seem to have stopped.

Thanks; fortunately we don’t currently have a drip problem.

Never suggested you did, heavens forbid :joy:
You described the situation of the flu exiting under a lean to roof? That would be against regs as it should exit into clear air. If you extend the flu to do this it will need to pass through the lean to roof hence the need for a flashing type seal to ensure you dont get drips passed the flue pipe.


I’ve changed that setting to ‘daily’ for you. It was set at every 4320 days for some reason! You can alter it in your prefs page.

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Oh thanks so much - how bizarre! And its working, I received this email.

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Ah, understood Corona,that will be why the plumber is concerned. Thanks for the advice.