APP membrane was first noted in Italy by Romolo Gorgato in 1967 and was usable in Holland and Great Britain by the mid-1970s. By the mid-1980s, it had approximately 90% of the market in Italy and 60% of France and Norway.
APP membrane is bituminous membrane modified with APP polymers. APP stands for Atactic Polypropylene which is a waterproofing membrane synthesized from modified bitumen with the addition of plastomers.
These membranes support remarkable tensile strength with maintaining their significant flexibility even in the coldest habitats. They can form a uniform matrix within the asphalt. This increases the bitumen’s achievement by enhancing its UV resistance, increasing its flexibility at low temperatures, and developing its flow resistance at high temperatures. Actually it has better durability, plasticity, resistance to low temperature, high temperature and ageing. Also with some kinds of them which are used for roofing purposes (coated with a tenancy blend of asphalt and atactic polypropylene), constructors nowadays have an adequate condition of application by heat welding. These membranes are about twice as thick as a traditional BUR cap sheet.
APP membrane is made up of Bitumen. Bitumen is a kind of waterproofing and road building substance that has been used in various forms. A waterproofing membrane is a thin layer of water-tight material that is put over a surface. This layer is extended and does not permit water to pass through it. We can use these membranes over terrace slabs and balconies, in concrete water tanks, in swimming pools, beneath and around basements and also over landscaped concrete decks. Actually by adding other materials to the bitumen, companies can provide a longer-lasting, more durable product – giving it either plastic or rubber properties. Modifying bitumen makes it qualified to resist a wide temperature range, and remarkable weather proofing.
The most general modified bitumens are APP membranes .
APP membrane should be stored in a vertical situation and during transportation handling should be continued in the same position and also they should be escaped stacking any materials on the rolls. We should assure that stocked packets are kept away from heat origins and ultra violet rays. Any keen gadget or membrane damaging operations should be kept out of the application surface due to defeat leakages.