Field test of dehumidifiers for avoiding condensation in unheated historical wooden houses

A field test of sorption dehumidifiers in the UNESCO World Heritage site 'Decorated Farmhouses of Hälsingland' successfully mitigated condensation risk, a threat to valuable wall paintings. The study found that dehumidifiers, programmed to limit indoor relative humidity (RH) to 80%, effectively prevented condensation across all rooms despite high air change rates (~0.8 ACH). While RH peaks occurred locally and temporarily due to transient wind or stack conditions, the overall effectiveness was demonstrated through climate logging and tracer gas measurements. The research provides practical guidance for dehumidifier installation in unheated historical wooden structures, balancing preservation needs with environmental control.

Mattsson, M., Akander, J., & Björling, M. (2025). Field test of dehumidifiers for avoiding condensation in unheated historical wooden houses. E3S Web of Conferences, 672, 5005. https://doi.org/10.1051/e3sconf/202567205005