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Wood fungi create vast damage among standing trees and all types of wood materials. The objectives of this study are to (a) characterize the cell materials of two major wood decay fungi (Basidiomycota), namely, Trametes versicolor and Postia placenta, and (b) compare the cell materials of decay fungi with four wood mould fungi (Ascomycota), namely, Aureobasidium pullulans, Alternaria alternata, Cladosporium cladosporioides, and Ulocladium atrum. Fourier transform infrared (FTIR) spectroscopy is used to characterize the microbial cellular materials. The results showed that the IR bands for the fatty acid at ∼2900 cm−1 were different for the two-decay-fungi genre. Postia placenta shows more absorbance peaks at the fatty acid region. Band ratio indices for amide I and amide II from protein amino acids were higher for the mould fungi (Ascomycota) than the decay fungi (Basidiomycota). Similarly, the band ratio index calculated for the protein end methyl group was found to be higher for the mould fungi than the decay fungi. Mould fungi along with the decay fungi demonstrated a positive correlation (R2=0.75) between amide I and amide II indices. The three-component multivariate, principal component analysis showed a strong correlation of amide and protein band indices.

Attenuated total reflection Fourier transform infrared spectroscopy is used in this study to quantify wood degradation. Nine different types of wood materials were studied. All types of wood were exposed in an Atlas solar simulator against artificial climate conditions. Additionally, natural climate exposure was performed for all types of wood at an outdoor test site in Trondheim, Norway, for 4 years. Surface treatment enhanced the durability of the wood and their performance against weathering. Rough surfaces might reduce the resistance against degradation in comparison with planed surfaces. The degradation during climate exposure created loss of lignin and accumulation of cellulose at the surface.

Claddings or façades are the outer part of building envelopes. In this study, wooden claddings are exposed to natural and accelerated weathering. The natural climate exposure was performed at a field test site located in Trondheim,Norway. Accelerated climate exposure was performed in the laboratory in an Atlas SC600 MHG solar simulator.Attenuated total reflectance -Fourier transform infrared (ATR-FTIR) spectroscopy was used to characterise surfaces.The objective was to assess degradation by use of FTIR and thereby see how this may be applied to evaluate the service life of wood. Four types of wooden materials were studied; three untreated and one treated with chromated copper arsenate. Surface concentrated cellulose and lignin are the primary wood components used to determine the quality and durability of wood during ageing. It was found that treatment with preservative chemicals and surface roughness has definitive impacts on cladding surfaces and change to the chemical properties of the materials during ageing. The acceleration factor deduced from the Arrhenius equation shows that an increase in temperature lowers the service life of cellulose at a higher rate than the other wood components.