The use of a pre-glued underlay will decrease installation time of solid and engineered wood flooring by up to 60%, this style of roll has a built in DPM membrane allowing it to be used over concrete and mineral based sub floors. The flooring is laid and set into the backing of the underlay which is covered with a high quality, high tack adhesive, once laid the flooring can be walked on immediately as no drying time needs to be allowed for, check out the installation video if you have ever seen this style of underlayment. Designed to reduce cost and increase speed this is the better option to select over more traditional methods.