Boiler Flue Regulations ensure that every installation is carried out safely, allowing Carbon Monoxide and other toxic gases to escape without putting others in danger. A boiler flue can be horizontal or vertical, but the position will need to be discussed and decided between you and your installer.
Other regulations include your property’s boundary line – the distance between this and your boiler flue will need to be at least 60cm, as well as being at least 2.1m off the ground
Knowing your way around these Boiler Flue Regulations can really help with the planning stage of your new installation.
You’ll get answers to all those burning questions you might be afraid to ask in this article, like ‘What does a boiler flue do?‘, ‘What installation restrictions are there?‘ and ‘Will I need an engineer?‘
Boiler Flue Regulations are put in place for health and safety reasons, and you’ll need to know why. They’re more than just a black duct sticking out of your house – they also keep us safe from harmful gases.
Read on to find out how boiler flue regulations keep your central heating system efficient and safe – it doesn’t have to be complicated!
What is a Boiler Flue and what does it do?
A boiler flue is the large pipe that leads dangerous gases from your combi boiler out through the wall or roof. They ensure that combustion fumes are discharged carefully and safely into the atmosphere and with the boiler flue regulations, are vital to your central heating system working effectively. You can think of it like an exhaust pipe for your house, working hard throughout the year.
However, the position of your flue needs to be specific so that there’s no safety risk for those nearby.
Why are there boiler flue regulations?
These boiler flue regulations are put in place to make sure that all installations performed are safe. The flues can be fed through the wall horizontally or through the roof vertically, but this will be discussed in more detail with whoever’s installing your new heating system. The regulations themselves are becoming stricter to ensure complete safety from the Carbon Monoxide being dispersed outside.
For an informative NHS guide on the risks of carbon monoxide, click here.
As mentioned, you’ll have to consider where your flue is going in relation to the surrounding environment. For example, think about where the boundary line is for your property – the boiler flue will need to be at least 60cm away from this. If not, then the installation won’t be allowed. Read on to find out more about boiler flue regulations.
Boiler Flue Regulations – Height
If you live in an end-terraced property and your horizontal flue is being installed near a public footpath, keep in mind how far it is from the public. It needs to be at least 2.1m off the ground for the gas to escape at a safe distance and to be declared safe. The temperature of these escaping gases will be extremely high, so it’s easy to see how these regulations can keep every installation safe!
If a flue is installed through a wall, it makes it a lot easier to seal and make water tight. An experienced engineer will always try to keep you as informed as possible.
Boiler Flue Regulations – What about vertical flues?
As well as being installed horizontally, flues can be installed vertically through a roof, but come with their own issues. If you’re getting one installed, make sure that you’re kept informed by a professional.
The flue has limited access if it’s installed vertically. To overcome this, access panels will need to be installed across the flue pipe. This will always come in handy for future work as the panels will provide access for servicing or location faults.
Boiler Flue Regulations – What else is done to make sure the installation is safe?
If you feel a bit clueless about this, try and familiarise yourself with some key points for when a flue is installed through a wall:
- The flue must be completely sealed on both sides – This is done using sand cement, caulk or other sealants to make sure that no gases can escape.
- The angle needs to be correct – this is more important if you’re going from a non-condensing boiler to a condensing boiler. If it’s wrong, then you may have a drip escaping.
- Screws are used to secure any joints – All extensions, brackets and pipework need to be properly fixed together otherwise joints become loose and dangerous.
- Ensure both parties understand the exact length of the flue – When adding extensions or bends to the flue, you’ll need to be made aware by the engineer of how far it will run. For example, a 45 degree bend will add another metre to the overall length.
Also be aware that if too many extensions are added, there’ll be too much flue distance for the gases to escape and your boiler won’t be able to perform at maximum capacity. Maximum flue length does change between each boiler as well.
For example, for the Viessmann Vitodens 050-W 29kw it is 15m, but the 35kw version has a maximum of 20m. This is down to health and safety reasons, but every manufacturer will have their own criteria. For this example we’re just talking about the reliable Viessmann brand.
Boiler Flue Regulations – How much do flue extensions cost?
Details of flue extension costs should always be covered in quotes you receive so that you know exactly what you’re getting at the end.
However, you can always use the following details for a vertical flue as a basic outline of what you might be charged for.
The average vertical flue needs:
- 1 x Vertical Flue Pipe – £63
- 1 x Lead Slate – £30
- 3 x Flue Extensions – £22 each
- 3 x Flue Brackets – £15 for both
- 2 x 45 degree bends – £35 for both
- 1 x Firestop Plate – £10
*These prices are a guide only and are subject to change depending on the retailer.
Boiler Flue Regulations – Will I need to replace my old boiler?
If you find that the flue on your old boiler is too low or too close to a neighbouring window, then you may need to make changes to your heating system. It’s not always necessary to get a new boiler at this stage, because some regulations only apply to new installations. However if you are looking to get a new boiler, you can get yourself a free, online quote from us today by entering your postcode below.