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1.2 Chimney pot
The top of the chimney flue must be equipped with a device, called a chimney cap, which facilitates
dispersion into the atmosphere of combustion products.
The chimney cap must meet the following requirements:
•
Its internal section and shape must be equivalent to that of the chimney flue.
•
Have a useful outlet section no less than double that of the chimney flue.
•
Chimney caps that emerges from the roof or which remain in contact with the outside (for example
in the case of an open loft), must be covered with brick elements and well isolated. It must be
constructed so as to prevent penetration into the flue of rain, snow, or foreign bodies and so that,
in the event of winds in any direction and at any angle, it assures the discharge of combustion
products (windproof chimney cap).
•
The chimney cap must be positioned so as to guarantee an adequate dispersion and dilution of
combustion products and, in any case, outside the zone of reflux. This zone can be different sizes
and shapes depending on the angle of slope of the roof, so it is necessary to adopt the minimum
heights shown in Fig.3 and Fig.4.
•
The chimney cap must be of windproof and exceed the height of the ridge, Fig.3 and Fig.4.
•
Any buildings or other obstacles that exceed the height of the chimney cap must not be close to
the chimney cap itself (Fig.3).
Fig.3
Fig.4
Fig.5
