Lumberjack 650 is a standard setting, hybrid polymer, trowel applied adhesive, specially designed for fixing all types of wooden floors directly on to all common substrates. Lumberjack 650 has the following key benefits: 100% active, solvent and water free, will not cause warpage of wood. Extended open time, of one hour, for large scale applications, permenantly flexible, suitable for use with underfloor heating, excellent gap filling properties for uneven surfaces, excellent acoustic properties.