Pyrolysis - the chemical decomposition of a substance by the action of heat
Safety message
Consider using a HETAS approved installer for wood burners and chimney liners.
They will ensure that the installation conforms to building regulations approved document J and issue a Certificate of Compliance.
Consider fitting a carbon monoxide alarm, which is now compulsory with all new installations.
Make sure your chimney is swept regularly and the flue liner is maintained in good condition.
How this fire happened
Timber adjacent to wood burner flue caught fire spreading to roof and causing extensive damage to the living room, roof and property resulting in a four pump fire.
The fire was extinguished using Schmitz ONE SEVEN foam and 2 high pressure hosereels.
A low heat source (120ºC - 200ºC) such as a flue or pipe applied to wood over a period of time in a confined space, has the effect of drying out fresh wood to a "cooked" state and causes the timber to ignite at temperatures far below its usual ignition temperature.
In this circumstance the heat from the flue has been sufficient to ignite the timber surround having undergone pyrophoric action.
Ordinarily the ignition temperature of soft wood is likely to be in the region of 250ºC, however, there are examples where temperatures as low as 77ºC have been sufficient to ignite timber subjected to pyrophoric action
(Ignition Handbook, V Babrauskas, Fire Science Publishers, 2003).