The objective of the SERVOWOOD project was to develop and establish European Standards that will facilitate the prediction of service life for exterior wood coatings. One of the objective of this project was to study fungal growth of the field exposed panels. Two coatings applied in 2 and 3 coats were exposed for one year outdoors at 45° south: one solventborne (alkyd based) and one waterborne (acrylic based) both in clear and pigmented versions. Fungal growth visually assessed was compared to fungal enumeration and the influence of exposure time on the main fungal species was studied. Results clearly showed that a lower fungal growth was observed on pigmented coatings. Despite the clear solventborne coating included a higher amount of biocide it was more susceptible to blue stain than the pigmented recipe. A new multifaceted exposure rig (MFER) designed for the project also contributed to the study of fungal growth. It allowed samples to be exposed with 9 different exposure directions and angles. The exposure using this MFER has shown that the worst cases (high area and high intensity of blue stain) were for samples with the clear coating exposed to north 45° and at the top of the MFER (horizontal surfaces). For any cardinal direction all surfaces inclined at 45° displayed more blue stain than vertical surfaces due to higher moisture content.

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