Influence of using treated wood on thermal properties and heat losses in basements of wooden buildings

Influence of using treated wood on thermal properties and heat losses in basements of wooden buildings

Paper in proceedings (conference paper)

In recent years an increasing attention has been paid on using of renewable natural and harmless materials in building constructions, particularly in the sustainable buildings. Utilization of wood as a material fulfils many sustainability criteria. This suggests the increasing ratio of wooden structures alone or in combination with solid structures as brick or concrete. Apart from many benefits, utilization of wood has also some specific problems which need to be dealt with. The design of joints of the timber wall on the foundation often carries the risk of defects such as unwanted uptake of water from the parts in contact with foundation or even soil, cracks, thermal bridges causing condensation and subsequent fungal growth and overall increment of heat loss of the building. All these factors can affect the quality of indoor environment, such as thermal comfort and air quality. For the long term service life of timbers used in wood structures and maintaining the good indoor environment a perfect wood treatment could be a solution. This paper describes the differences in thermal properties of the external wall of a wooden building construction connected to the monolithic concrete foundation with respect to different moisture content of a construction wood. The influence of this moisture content on the heat transmittance of a building envelope external walls with two types of spruce commonly used for timber structures were studied. Thermal conductivity experiments were carried out on several specimens of untreated and treated spruce with different density and moisture contents. From these experiments required values needed for numerical simulations were obtained.

In recent years an increasing attention has been paid on using of renewable natural and harmless materials in building constructions, particularly in the sustainable buildings. Utilization of wood as a material fulfils many sustainability criteria. This suggests the increasing ratio of wooden structures alone or in combination with solid structures as brick or concrete. Apart from many benefits, utilization of wood has also some specific problems which need to be dealt with. The design of joints of the timber wall on the foundation often carries the risk of defects such as unwanted uptake of water from the parts in contact with foundation or even soil, cracks, thermal bridges causing condensation and subsequent fungal growth and overall increment of heat loss of the building. All these factors can affect the quality of indoor environment, such as thermal comfort and air quality. For the long term service life of timbers used in wood structures and maintaining the good indoor environment a perfect wood treatment could be a solution. This paper describes the differences in thermal properties of the external wall of a wooden building construction connected to the monolithic concrete foundation with respect to different moisture content of a construction wood. The influence of this moisture content on the heat transmittance of a building envelope external walls with two types of spruce commonly used for timber structures were studied. Thermal conductivity experiments were carried out on several specimens of untreated and treated spruce with different density and moisture contents. From these experiments required values needed for numerical simulations were obtained.

Wooden building, treated Spruce, untreated Spruce, thermal conductivity, thermal simulation

Wooden building, treated Spruce, untreated Spruce, thermal conductivity, thermal simulation

VAHALOVÁ, E.; PEUHKURI, R.; ŠUHAJDA, K.

2014

09.09.2013

RSA, Vienna, Austria

Vienna, Austria

978-3-85437-321-6

Proceedings of the 2nd Central European Symposium on Building Physics (CESBP 2013), Contributions to Building Physics

847

854

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