The surface shall be cleaned thoroughly of all contaminants like dust, traces of curing compound, oil and grease. All surface imperfections, protrusions, structurally unsound and friable concrete must be removed and repaired with a suitable POLYCRETE* concrete repair mortar.
Apply POLYPRIME SB* (Solvent based primer) @4-6 m²/lt to a clean, smooth and dry surface by brush, roller or spray. Allow the primer to dry prior to the application of the membrane. As the viscosity of
the primer is low, it easily penetrates into the concrete pores. The primer promotes the adhesion between the membrane and the concrete surface. In addition to that, the primer also acts as a binder for the dust particles which gets accumulated on the concrete surface even after cleaning.

Bituplus G 4140 membranes are installed by using a cylinder fed propane gas torch. use of handheld roofing torch is recommended as it affords a good control. if multiple burner torching machines are utilized, care must
be taken to ensure the application of uniform heat and avoid overheating of the membrane. Begin torching the embossed polyethylene side of the rolled portion of the membrane. proper torching procedure involves passing the torch flame in an “L” pattern applying about 75 percent of the heat across the coiled portion of the roll and 25 percent across the substrate, including the lap area of the previously installed membrane. As the membrane is heated the embossing starts to melt away exposing a shiny bitumen surface. Roll forward the membrane and press firmly with the boot or roller against the substrate to bond well. The propane flame should be moved from side to side and up the lap edge while the membrane is slowly unrolled and adhered to the underlying surface. Subsequent shift of the roll shall be avoided after heating has begun. When complete, the remaining untorched membrane shall be re-rolled and installed in the same manner. When one end is complete, re-roll the opposite end not yet torched, and install in the same manner. as subsequent rolls are installed, heat is applied to both the roll and the exposed laps of themembrane being overlapped onto. Be sure to heat the entire roll evenly, not just the lap areas, with extra concentration at the laps. CAUTION: do not over torch as this will expose the reinforcement in the membrane and cause damage to it 

All angles and abutments should be sealed with extra care to ensure full bonding. Bituplus G 4140 shall be lapped with the base membrane and taken up on the parapet wall and tucked into a groove cut into the concrete.the grooves shall be sealed with a suitable mastic sealant (Bitumastic).