tiiveysmittauksia

Tiiveysmittauksia, often translated as airtightness testing or building envelope testing, are procedures used to measure the degree of air leakage in a building's external envelope. The primary goal is to quantify how much uncontrolled air is entering or leaving a building through unintentional gaps and cracks in the construction. This is typically done using a blower door, a powerful fan that is temporarily mounted in an exterior doorway.

The blower door fan either pressurizes or depressurizes the building to a standardized pressure difference, usually 50 Pascals. During this process, all intentional openings like windows and doors are sealed. Sensitive measuring equipment then records the volume of air that the fan needs to move to maintain this pressure difference. This airflow rate, often expressed in cubic meters per hour per square meter of building envelope area (m³/h/m²), is the key indicator of the building's airtightness.

High levels of air leakage can lead to several problems. It can significantly increase heating and cooling costs as conditioned air escapes and unconditioned air infiltrates. It can also cause discomfort due to drafts, contribute to moisture problems within building assemblies, and negatively impact indoor air quality if uncontrolled air carries pollutants. Conversely, a well-sealed building envelope is crucial for the effective performance of mechanical ventilation systems, which are designed to provide controlled fresh air.

Tiiveysmittauksia are a standard part of building regulations and energy performance certifications in many countries. They help building professionals identify and address potential air leakage issues during construction or renovations, ensuring better energy efficiency, comfort, and durability of the building.