Kondensrisk

Kondensrisk, literally "risk of condensation" in Swedish, denotes the likelihood that water vapor will condense into liquid on surfaces or within building assemblies when air at a given temperature and moisture content cools to its dew point. The concept is used in building physics, HVAC design and meteorology to evaluate potential moisture problems that can degrade materials, reduce thermal performance, and harm indoor air quality.

Causes of kondensrisk include high indoor humidity, inadequate ventilation, thermal bridges, insufficient insulation and large temperature differences between interior and exterior. Condensation may occur on cold interior surfaces (surface condensation) or inside walls and roofs (interstitial condensation), where it is harder to detect and can promote mold growth and structural decay.

Assessment methods range from simple dew point calculations and psychrometric analysis to the Glaser method and detailed transient hygrothermal simulations. Practitioners use these tools to identify locations and periods with elevated condensation probability, considering vapor pressure, relative humidity, material layers and thermal resistance.

Prevention and mitigation strategies focus on controlling moisture sources, maintaining balanced ventilation, providing adequate thermal insulation, avoiding thermal bridges, and using appropriate vapor retarders or breathable membranes depending on climate and construction. Good design also incorporates drainage and drying paths so any accumulated moisture can be removed.

Kondensrisk is a key consideration in renovation and energy-efficient construction because tighter building envelopes can increase moisture accumulation if ventilation and moisture control are not addressed. Regular inspection and monitoring of humidity and surface temperatures help manage ongoing risks.