Effectiveness of finishes in protecting wood from liquid water and water vapor

Abstract

Wood is increasingly used in the bathrooms for furniture due to its beauty, warm and organic look, but also for floors, walls, and even for wooden sinks and bathtubs. Wood in the bathroom is exposed to changes in temperature and humidity as well as spillage and splashing of water and should therefore be properly finished with an effective coating to protect it from extreme changes in moisture content. In this research ash and larch wood were finished with penetrating and film-forming coatings and subsequently were exposed to liquid water and water vapor. During exposure to liquid water and water vapor, the mass of the samples and the moisture content in the samples were measured. Results showed that penetrating coatings provided some protection against liquid water absorption but very little protection against water vapor, especially on ash wood. Moreover, the moisture excluding effectiveness reduced rapidly during exposure to high humidity and depending on the wood species and coating systems. • Wood species did not affect liquid water uptake of wood finished with an alkyd film-forming system. • Penetrating coatings should be used in the bathroom only on durable wood species. • Penetrating coatings provided some protection against liquid water absorption, but they provide very little protection against water vapor. • Moisture excluding effectiveness reduced rapidly during exposure to high humidity and depending on the wood species and coating systems.