Distance To Combustibles

Due to the high levels of heat emitted from flue pipes and stoves it is essential these are installed at a safe distance from any combustible material. The clearances required vary from Single to Twin Wall flue and are controlled by building regulations and despite some seeing them as a nuisance to their installation, they are designed to keep you safe and protect the construction of your property. For stoves, the safe distance is determined by the manufacturer and recorded on the data plate.

As these have no insulating material, Single skin pipes lose a lot of their heat and become very hot on the outer surface. It stands to reason that to be safe you must maintain quite a substantial distance between these and combustible materials. Building Regulations state this clearance must be at least 3 x the diameter of the flue pipe as illustrated below. If the surface is constructed from a non-combustible material or you have shielded it with fire proof boarding such as our Vermiculite Boards, then this distance can be reduced to 1.5 x the diameter of the flue pipe.

SW Distance to Combustibles

Due to the 30mm layer of compressed Rockwool insulation within these pipes, the heat emitted from a Twin Wall flue is greatly reduced and so is the safe clearance to combustibles. For our Convesa Twin Wall, this distance must be at least 60mm. This figure is included within the designation number applicable to your brand of Twin Wall pipes. There is no regulation for the distance of Twin Wall flue pipes to a non-combustible material.


Stoves require the greatest clearance to any potentially combustible material but this does come down to the individual brand and model of appliance and is stated on the data plate. This measurement could be in the region of 600mm, 800mm or even greater and may be different for the sides and rear. There is no regulation for the distance of a stove to a non-combustible material, only clearances recommended by the manufacturer (usually in the region of 100mm to allow air to pass around the appliance).

Data Plate

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