Prefabricated modified polymer-bitumen membrane composed of distilled bitumen and elasto-plastomers (APP) reinforced with a woven non woven single strand composite polyester fabric. The upper face of the membrane is coated with the waterproofing mass and protected with a PE film, while the lower face is the exposed reinforcement. The characteristics of the membranes in the NORD BASE range allow them to be used with success as a regularisation layer, as a first layer mechanically fixed to wooden roofs, as a vapour diffusion layer, as a separation layer between bituminous membranes and synthetic ones as well as in several other applications.