ilmanpitävyystestiksi

Ilmanpitävyystesti, known in English as an airtightness test or blower door test, is a procedure used to measure how airtight a building is. It quantifies the rate at which conditioned air escapes from a building and unconditioned air enters. This is typically done by depressurizing or over-pressurizing the building using a fan mounted in a doorway, while simultaneously measuring the airflow required to maintain that pressure difference.

The primary purpose of an ilmanpitävyystesti is to assess the building's thermal performance and energy efficiency. Air leakage can be a significant source of heat loss in winter and heat gain in summer, leading to increased energy consumption for heating and cooling. By identifying and quantifying air leakage, builders and homeowners can pinpoint areas where insulation or sealing improvements are needed.

Beyond energy efficiency, airtightness is also crucial for indoor air quality and building durability. Excessive air leakage can lead to moisture problems, which in turn can cause mold growth and damage to building materials. Furthermore, uncontrolled air movement can introduce pollutants from outside into the building. Regulations in many countries require buildings to meet certain airtightness standards, often verified through these tests. The results are typically expressed as air changes per hour (ACH) at a specific pressure difference, such as 50 Pascals.