Different strategies to control humidity in Swiss low energy buildings

For the approximation of the internal loads of humidity, too high values are often chosen inSwiss low energy houses. Later on in reality, the occupation and the presence in the dwellingsare significantly lower. These leads to high specific air volume rates and consequently to lowhumidity levels. Humidification by vapour generators, humidity recovery and optimized air volume rates are currently applied. Engineers can now calculate the internal humidity loads without humidity storage in walls etc. They can chose of humidity recovery and/or a vapour generator and set minimal and maximum values for relative humidity. The calculation of the resulting relative humidity and the consumption of electricity and water for the vapour generation are presented in figures. Simulations with IDA ICE have shown that the control strategy with humidity recovery had higher resulting relative humidity than the control strategy with the reduced and optimised air volume rates