ECOSAFE – Moisture safe and eco-friendly timber structures with sawdust based insulation

Sawdust based insulation has many benefits, which allow for moisture safer structural solutions, that are also eco-friendly, healthy and industrially producable. Sawdust based insulation has a high moisture capacity, which reduces the risk of moisture damage in the structure during use, improves the fault tolerance if air leakage occurs, and reduces the need to use anti-mildew compounds and chemicals. Since the insulation is wood based, it also lowers the carbon footprint of structures, which can be used to compensate for the lower thermal insulation capacity.

In the ECOSAFE-project the hygrothermal performance of sawdust based structures is studied both experimentally and by calculation. Additionally, the requirements for making the structures moisture safe without anti-mildew compunds or a vapour barrier are studied in current and future climate conditions. During the analyses the hygrothermal performance of the sawdust insulated structures is compared to that of current energy efficient structures. The structures included are exterior walls, roofs and base floors from both single-family houses and larger timber-frame buildings. During the project, building physical material properties are also determined for the sawdust based insulation materials, so that their hygrothermal performance can be analysed more accurately by calculation. As a result of the study, recommendations and structural solutions are complied for building moisture safe sawdust insulated structures.

During the project the carbon footprint of sawdust insulated external structures is compared with that of structures, which fulfill the current energy efficiency regulations. The U-value requirements needed for the carbon footprint of sawdust insulated structures during their lifetimes to be lower than that of current energy efficient structures are determined. The analyses are done using the Ministry of Environment’s new calculation method for the carbon footprint of a building during it’s lifetime. As a result of the study recommendations for the reference U-values of these structures are determined.

The project spans from 2019 till 2021.