According to the UNI 7129 standard strong> the chimney pot has to respect some requirements:
- must have a double outlet section compared to the chimney.
- must prevent the entry of rain and / or snow
- must ensure the discharge of the products of the fumes even in the presence of winds coming from different directions.
The chimney has as main task that of the fumes produced and must be unique on a single flue.
The draft of the fumes can often be altered by the wind coming from different directions and therefore it will be necessary to make some changes to the chimney.
First of all, the chimney's mouth is important to be positioned in full wind and at a height of one meter higher than the roof ridge considering that the chimney's openings are at least twice the chimney section.
To avoid this problem we can:
- Apply a sort of protective hat called "myrrh" that allows you to "break the wind".
- Apply normal smokestacks that shrink on the bottom
- Identifying the direction of the winds, you can intervene by breaking the wind by completely plugging the two sides exposed to the wind and giving the other two sides of many openings. The more the area is windy, the more the holes must be small.
- To orientate the bricks with which the chimney is constructed differently. Also in this case the section for the fumes outlet must be at least double of the flue.
Today the "windproof" chimneys are equipped with wing profiles to guarantee good disposal of the fumes produced by combustion.