Waterproofing in Compliance with DIN 18531

The DIN 18531 series of standards, “Waterproofing of Roofs, Balconies, Loggias, and Pergolas,” has been in effect since July 2017. It replaces parts of DIN 18195, “Waterproofing of Structures—Terminology.” Whereas DIN 18531 previously dealt only with the waterproofing of unused roofs, it now also covers used roofs, roof terraces, and green roofs. The guideline has also been expanded to include the areas of balconies, loggias, and pergolas from the former DIN 18195-5.

DIN 18531 is structured as follows:

Unused roofs include flat and sloped roofs that are accessed solely for the purpose of care, maintenance, and general upkeep. Roof surfaces with extensive greening are also classified as unused roofs according to DIN 18531. Used roofs include accessible areas, such as roof terraces, as well as those with intensive greening.

DIN 18531 specifies which waterproofing materials may be used in the various areas. These include liquid-applied waterproofing systems with and without an integrated wear layer, such as those we at Triflex offer with our polymethyl methacrylate (PMMA)-based systems. DIN 18531 certifies these systems as suitable for all areas of application. Important to note: The liquid polymer solutions must have a European Technical Assessment (ETA) based on ETAG 005. This also applies to directly accessible, used roofs such as roof terraces, although an integrated wear layer is additionally required in these cases. This consists of an additional layer with a top sealant, which can be sprinkled with plastic chips or quartz sand, if necessary, to ensure safe foot traffic.

Furthermore, DIN 18531-1 distinguishes between two classes of roof waterproofing depending on the intended use: Class 1 is limited to standard roof structures, for which the waterproofing material must meet the minimum requirements. For demanding structures that fall under Class 2—such as high-rise buildings—stricter requirements apply to

In this way, DIN 18531 ensures a long service life for the materials with increased reliability and, at the same time, low maintenance requirements. The Triflex ProTect fabric-reinforced roof waterproofing system and the Triflex ProDetail detail waterproofing system meet all requirements of Application Class 2.

For balconies, loggias, and pergolas as well, DIN 18531 specifies, among other things, liquid-applied membranes with a European Technical Assessment (ETA) based on ETAG 005, both with and without reinforcement. Furthermore, coatings with surface protection systems of classes OS 8, OS 10, and OS 11 are deemed suitable in accordance with the Guideline for the Protection and Repair of Concrete Structures (RL SIB). The OS 8 balcony coating system Triflex BFS ensures the secure integration of all connections—such as to doors, drainage channels, or railings—thanks to the integrated detail waterproofing Triflex ProDetail with a special nonwoven fabric insert. The system is also available in a flame-retardant version (S1). Thanks to its low weight per unit area and thin layer structure, it is ideal for renovation projects. The surface can be designed in many variations and colors, ensuring that aesthetic requirements are also met.