Analysis of rot on building materials

Aims

Wood and wood-based materials that are exposed to excess amounts of moisture are at risk of being degraded by certain types of fungi and bacteria. Microbial rot can affect the stability and strength of a material, as well as cause cracks in which other microorganisms can grow. Our service, analysis of rot on building materials, assesses the occurrence and distribution of rot in various materials. The service is used to analyse the degradation of building materials from buildings, constructions, and deep foundations with suspected degradation. Other materials can also be analysed, such as piles or separate wooden objects.

The service can also be used for status assessment of wooden foundations. Even wood that is used within its intended setting​​, such as in wooden foundations, is at risk of degradation due to wood rotting fungi if the exposure conditions in its environment change. Damages to foundations or built-in structural timber can go without detection for several years, as visible damages to overlying structures only appear when the affected material can no longer support its intended load. For larger construction projects with an impact on the local environment which risks exposing structures to increased degradation, it can therefore be beneficial to carry out an analysis of the status before start of construction. The analysis results can then be used as documentation, in case of a possible future dispute, for the condition of the foundation before the local environment change.

Method

The analysis is carried out according to a well-proven method that is used both in Sweden and internationally. Decomposition of the material by wood rotting fungi and bacteria is assessed and quantified using a microscope. The scope of the attack is classified according to:

• No occurrence: no traces of degradation
• Sparse occurrence: initial degradation
• Moderate occurrence: established degradation
• Abundant occurrence: well-developed degradation
• Complete degradation: no healthy cells remain

Delivery

The analysis results are presented in a written report, together with interpretation guidance. Note that the analysis provides a result that is indicative of the status of the analysed sample, not the entire construction. Suggestions for potential remediation efforts for the construction or the object can therefore not be made based solely on the analysis results. Wood rot analyses also cannot assess the mechanical strength of the sample as the relationship between decomposition and mechanical strength is not linear.