AS/NZS 4548.1:1999 (R2013) PDF Download

AS/NZS 4548.1:1999 (R2013) is a standard that serves as a guide for long-life extensible coatings for concrete and masonry walls. These coatings are intended for use on both exterior and interior surfaces and are applied using airless spray or roller methods, following the manufacturer's instructions. The paints covered by this standard fall under paint Type 38 of AS 2311 and the Australian Paint Approval Scheme specification Type 2 of GPC-C-117.

Latex extensible wall coatings, commonly known as membrane coatings, are flexible and watertight finishes applied to prevent moisture infiltration. They retain flexibility even at varying temperatures, allowing for expansion and contraction of the substrate. These coatings also offer anti-carbonation resistance. However, they are not suitable for horizontal surfaces where water ponding might occur. It is typical for these coatings to be used as part of systems involving a sealer and multiple coats.

Application of membrane coatings can be done using airless spray, textured roller, or nap roller, with a recommended spreading rate of 1.0-2.0 m²/L (1.0-0.5 L/m²) per coat. The total film thickness applied plays a crucial role in achieving the desired performance levels, particularly in terms of crack bridging, where higher film thicknesses enhance this property.

The standard also includes two notes: the first note highlights that AS/NZS 4548.5 provides a test to verify the cure of concrete and masonry surfaces before applying the sealer, while the second note, provided in Appendix A of the standard, offers guidance on the use of long-life coatings for concrete and masonry.