lämpötiiveyden

Lämpötiiveys, often translated as thermal tightness or airtightness, refers to the degree to which a building envelope prevents uncontrolled air leakage. This uncontrolled air movement, both infiltration (outside air entering) and exfiltration (inside air escaping), can significantly impact a building's energy performance, comfort, and indoor air quality. A well-sealed building envelope minimizes these air leaks, creating a more stable and predictable internal environment.

The concept of lämpötiiveys is crucial in modern construction, particularly in energy-efficient building designs. By reducing air leakage, buildings require less energy for heating and cooling because conditioned air is retained inside and unconditioned air is kept out. This also helps to prevent drafts and uneven temperatures, enhancing occupant comfort. Furthermore, proper airtightness is essential for the effective functioning of mechanical ventilation systems, ensuring that fresh air is supplied deliberately and exhaust air is removed efficiently. Without good lämpötiiveys, ventilation systems may struggle to achieve their intended performance, and moisture can be driven into building structures, potentially leading to mold and material degradation.

Testing for lämpötiiveys is typically done using a blower door test. This standardized procedure depressurizes or pressurizes the building to measure the rate of air leakage. Building codes and energy standards often specify maximum allowable air leakage rates to ensure a baseline level of performance. Achieving high lämpötiiveys involves careful detailing and execution of construction elements, including windows, doors, wall and roof junctions, and penetrations for services.