Timber-framed exterior walls insulated with wood shavings: A field study in a nordic climate

Wood processing residues provide a possibility to produce thermal insulation material with low environmental impact. This paper deals with the hygrothermal performance of timber-framed exterior walls with wood shavings as insulation material. The presented study consisted of field measurements of five exterior wall structures with two different types of wood shavings insulation and three reference walls. The study was performed in cold Nordic climate, where hygrothermal conditions at outer parts of a wall structure are critical. Untreated wood shavings and wood shavings coated with pulverized clay were compared as insulation materials. Different wind barriers as well as a water vapour barrier and sheathing acting as vapour retarder were also used. Results indicated no suitable conditions for mould growth inside any wall. The thermal resistance of wind barriers as well as the clay-coating of wood shavings had positive effect on the hygrothermal performance of the test walls. Wood shavings proved to be suitable insulation materials for well-insulated structures from the hygrothermal point of view, when the overall design, construction and maintenance are carried out in a proper way. •Performance of wood shavings as thermal insulation material in timber-framed exterior walls was studied in Nordic climate.•All the studied types of wood shaving insulation performed well and are worth of further studies.•Moisture buffer capacity of insulation improves the hygrothermal performance of a well-insulated exterior wall.•No negative effects of clay-coating of wood shavings insulation were detected during the study.•Thermal resistance of wind barrier was of paramount importance regardless insulation material.