Chimney Flue Maintenance
All flues should be checked for blockages caused by falling soot, bird nests or masonry debris - faults that will usually be revealed by sweeping. Sweeping should be carried out regularly - at least twice per year when wood or other solid fuels are being burnt, at least once each year if burning gas or oil. Acids or tars generated by wood or coal products are corrosive and can, in time, erode mortar or flaunching; any damage caused by this action can be found by survey as can other damage or holes which should be repaired promptly to prevent leakage of combustion gases into rooms or roof spaces. Air leakage into the flue will cool the gases, reducing updraught.
An efficient hearth must have a good air supply, a common cause of air starvation is excessive draught proofing or the use of double glazed replacement windows (the fitting of solid fuel or multifuel stoves should be carried out by a qualified fitter who will ensure that there is adequate ventilation). Additional venting may have to be fitted.
Use the proper fuel - for wood burning or multifuel equipment burn only seasoned hardwood - maximum 20% moisture content dried for at least one year.
When a cowl is fitted the fixings must be inspected periodically to ensure that the fasteners are tight, especially in areas subjected to high winds.