The more and more widespread need to reduce cement in towns, with intense greenery planted also to the light roofs of new estates, has brought with it the problem of the root resistance of waterproofing layers not protected with cement screed. The reason for its absence is due to its excessive weight, and the difficulty of applying it to pitched roofs.
Direct contact of the layer with the soil implies intrinsic resistance of its membranes against the perforating action of roots.
The use of membranes reinforced with metal foils or polyester film has often turned out to be a failure because the continuity of the mechanical protection on the sheet overlaps is not guaranteed. In some cases of waterproof coverings of roof gardens, which have been in place for some years, made up of two overlapped and offset layers, both reinforced with PET polyester film, the roots manage to get through the overlaps of both layers.
It is a root resistant waterproofing membrane. The antiroot properties are obtained by adding phenoxi-fatty acid ester, a specific antiroot agent, to the polymer-bitumen compound Once applied.
Defend Antiroot Polyster forms a continuous barrier against roots. As it does not contain film or double-reinforced foils.
Defend Antiroot Polyster is more flexible and malleable during application. The additive has been developed specifically as a root inhibitor, for both hot-laid bitumen and for torch-laid bitumen membranes.
Defend Antiroot Polyster is made up of distilled and selected bitumen for industrial use containing a high quantity of elastoplastomeric polymers such as to obtain a “phase inversion” alloy. The continuous phase of this alloy consists of the polymer in which the bitumen is dispersed, where the characteristics are determined by the polymer matrix and not by the bitumen, even if it is the largest ingredient. The performance of bitumen is therefore increased, durability and resistance to high and low temperatures are improved, thus maintaining the bitumen’s already excellent qualities of adhesion and waterproofing. The reinforcement of the membrane consists of a single strand Spunbond non-woven polyester fabric, with high basic weight (grammage). This fabric is isotropic, rot-proof, thermally fixed and boasts: high mechanical resistance, considerable ultimate elongation, excellent resistance to punching and laceration.
Defend Antiroot Polyster has both faces coated with Flamina, the hot-melt film, which stops the rolls of material from sticking.