27
MINIMUM
6" dia.
SOOT DOOR
ASBESTOS ROPE
PACKING
MINIMUM
150mm (6")
BRICK UP
APERTURE
FILL VOID

REAR FLUE OUTLET

ALL INSTALLATIONS MUST CONFORM TO THE BUILDING REGULATIONS
Reinstate brickwork around pipes using lime mortar, and make good.
Fill the space around the appliance level with the top unit with Vermiculite cement (6 parts Vermiculite granules
to 1 part Portland cement). The flue socket in the appliance is designed to receive 5'' or 6" nominal cast iron or
heavy duty steel pipe connector which should be caulked with asbestos rope and fire cement.
The length of the connector pipe will be dependent on the distance between the top of the appliance and the
bottom of the chimney but should be at least 300mm (12").
Fill the remaining space around the connector with the Vermiculite cement to a level where the pipe is
effectively sealed in the chimney flue, ensuring that the flue gases can only be discharged into the flue way.
Reinstate brickwork to chimney breast and make good. Remember to make provision for access to boiler
connections for routine observation/maintenance.
Replace parts previously removed and check unit thoroughly.
25. FLUES AND CHIMNEYS
Flexible stainless steel liners used on all oil and gas appliances are NOT suitable for solid fuel and MUST
NOT BE USED.
The diameter of the flue pipe should not be less than that of the appliance outlet.
If the flue dimensions are large, line the flue with insulated pipes to the point where the dimensions reduce. The
minimum diameter of any flue should be 125mm.
The Building Regulations set out minimum distances between the termination of the chimney and the roof,
including any roof lights.
A chimney may comply with the regulations but still be subject to down draught and similar problems. A
chimney terminating above the ridge level is generally less likely to suffer such problems.
Chimneys should be as straight as possible.
Horizontal runs should be avoided except where the rear outlet of the appliance is used, in which case the
horizontal section should not exceed 150mm (6'') in length.
An access to the flue for sweeping must always be provided, irrespective of the flue type. Purpose made soot
doors and inspection lengths are available from manufacturers of all systems.
Ensure that the whole length of the flue can be reached from the soot door.
For advice on flues and chimneys contact H. DOCHERTY Ltd. Tel: 0845 6031715.