EN 927-5 Paints and Varnishes, Coating Materials and Coating Systems for Outdoor Wood, Part 5: Evaluation of Water Permeability

EUROLAB laboratory provides testing and compliance services within the scope of EN 927-5 standard. This part of EN 927 specifies a test method for evaluating the liquid water permeability of cladding systems for exterior wood by measuring the water absorption of veneered wood panels. Results are expressed as grams of water absorption per square meter over a 72 hour period.

The treatment of external wooden surfaces has both aesthetic and protective functions. A vital purpose of a coating system is to protect the wood against aesthetic degradation (e.g. blue spot attack) and dimensional changes.

Because such attacks are mainly caused by the high moisture content in wood, knowledge of the relative water permeability properties of coating materials applied to exterior wood is helpful in selecting products for specific end-use applications as described in EN 927-1.

Water permeability is assessed by measuring the water uptake over a 72 hour period of a coated test panel exposed to liquid water.

The tested coating is applied to the face of a defined test panel, where the remaining face and edges are carefully sealed using a defined mandatory low permeability sealer.

EUROLAB assists manufacturers with EN 927-5 test compliance. Our test experts, with their professional working mission and principles, provide you, our manufacturers and suppliers, the best service and controlled testing process in our laboratories. Thanks to these services, businesses receive more effective, high-performance and quality testing services and provide safe, fast and uninterrupted service to their customers.