In order to allow optimum air circulation in all of these elements of a house, not only must all the guidelines contained in the architectural design be followed, but the materials used must also be compliant with requirements for ventilation. In case of roof accessories, it is necessary first to distinguish between a vent and a ventilation chimney. While the former is used to facilitate the ventilation of the premises, the latter is responsible for the proper operation of the sewage system. Seeing as construction standards provide different requirements for the parameters of sewage pipes and ventilation of rooms, different types of chimneys vary in diameter, height and finish. Interchangeable use of these two types of chimneys is a mistake that can adversely affect the ventilation performance.

The operation of the sewage system is usually based on gravity. Although other solutions are also used, the outflow of waste water into the external tank under its own weight is still the most popular solution. 

For impurities to flow freely, adequate atmospheric pressure must be maintained in the sewer pipes. Therefore, the drainage system must be terminated by a vented chimney, which allows the air pressure in the pipes to be equalized and the sewage gas removed. Neglecting this type of solutions can cause the air and with it, the unpleasant odors, to be forced into the interiors when draining sewage.

It is worth noting that both devices are also used because it is troublesome to keep a roof tight at the ends of sewer pipes or ventilation ducts. Properly selected chimneys also contribute to sealing of the roofing. Moreover, the option to accurately match their color to the color of the base tiles affects the aesthetics of the roof.

Arch. Dorota Palmączyńska

Design Studio Archipelag