Air tightness

Air tightness is the property or ability of a material, structure or system to minimize the penetration of air through unwanted gaps, cracks or fissures. It is an important factor in construction and the energy efficiency of buildings, as impaired air tightness can lead to heat leakage, increased heating and cooling costs, reduced indoor air quality and reduced comfort for residents.

Airtightness is measured using different methods, for example using pressure tests or smoking tests. The result is an expression of the amount of air that escapes through a given structure under certain conditions. This expression is often given in the value of air flow per square meter (m³/h.m²) or in the value of overflow or penetration (for example in m³/h or l/s).

Airtightness is often divided into internal airtightness and external airtightness. Internal airtightness refers to the tightness between spaces in a building, such as between different rooms, living units or different separate areas. External air tightness refers to the tightness between the building and the external environment, such as sealing between walls and windows, doors, penetrations or other external openings.

There are many factors that affect the airtightness of a building, including the quality and correct installation of sealing materials, joint sealing, the construction and design chosen, as well as the influence of external conditions such as wind, temperature and pressure. Properly achieved and maintained airtightness can lead to improved energy efficiency of buildings, increased comfort for occupants and better control of air flow and indoor air quality.

Air tightness is an important aspect in connection with the certification and evaluation of the energy efficiency of buildings, as well as in the fulfillment of standards and regulations related to air quality and energy management. Therefore, it is important to keep in mind and correctly implement measures to achieve the required air tightness in construction projects and building maintenance.