Rectangular tube: installation and maintenance recommendations

A good ventilation system must consist of a properly sized duct layout (it can be a rectangular tube or one with a circular section) that ensures that stale air, resulting from the normal and habitual use of the premises, is extracted from humid areas (kitchens, bathrooms, and laundry rooms) through the extraction points connected to the group. These ducts should be smooth, and if possible, anti-static and anti-bacterial. This way, dust and dirt will be prevented from accumulating inside, as well as the retention of particles (and consequently, the proliferation of microbiological agents that cause microbial contamination). These characteristics will minimize pressure losses to the maximum. An airtight duct network, besides ensuring greater energy efficiency, will prevent the entry of air and the noise they produce.

Recommendations

• We must ensure that this duct network is of easy installation and assembly. Therefore, it is recommended to install systems whose assembly is based on the mecano system, without putties or adhesive tapes, and that ensure perfect airtightness.

• If there is not enough space, a good solution is to install a flat rectangular duct network that adapts to any architecture. Whatever the nominal section, make sure that the ducts meet the fire resistance requirements according to UNE standards, that they withstand a maximum operating temperature of + 80º C, and that they provide the minimum ventilation flows necessary for which the installation was designed.

• The current regulations emphasize the importance of avoiding microbial proliferation. Thus, in the Regulation of Thermal Installations in Buildings (RITE, 2007), it is specified that "the materials used must not facilitate (or be nutrients for) microbial proliferation".

Maintenance of the duct network

In addition to ensuring that the interior of the ducts is smooth, as previously specified, to avoid the accumulation of dirt, they must be accessible (for sanitization and cleaning) every 10 meters along the entire route. The regulations, CTE DB HS3 Indoor air quality, also requires that cleaning operations be carried out in the ducts once a year and that their airtightness to air be checked once every five years. During cleaning operations, and as established by RITE, we must ensure that the interior linings of the ducts can withstand the aggressive action of the products used for disinfection and that the interior surface has a mechanical resistance that allows it to withstand the stresses that such mechanical cleaning operations imply.

The compliance with current regulations is the best guarantee that your ventilation system does not pose a threat to the comfort, well-being, and health of people. Make sure that the ventilation system of your building is in the hands of specialized professionals who accompany you throughout the process, from the design phase to the commissioning of the system.