But even the place a flue is already lined, old steel liners finally suffer from corrosion. In older properties, the stack partitions were built without adamp-proof course(DPC), and eroded mortar joints can permit damp to penetrate down through porous masonry. To forestall this, fashionable stacks have a DPC through the chimney at roughly 150mm above the roof and one other close to the top.

Flexiblesingle-skinned linersare used primarily for gasoline fires andoil or gasoline-fired boilers, whereas hardierdouble-skinned linersare required forburning stable fuels(i.e. for woodburners). Gaps could have additionally formed the place mortar joints have been eroded over time by acidic chemical substances from combustion gases. Leaks can generally go undetected, notably inside lofts or to adjoining houses. Theairtightness of a fluecan betestedusing smoke pellets (available from DIY stores). Where possible, leaky mortar joints should be made good previous to lining the flue.

Redundant flues also must be ventilated to forestall … Read More