SBS modified bituminous waterproofing membrane


BITUPLUS EX is a superior grade of bituminous waterproofing membrane manufactured by blending a mixture of bitumen and SBS (Styrene Butadiene Styrene) polymers to obtain excellent waterproofing and low temperature flexibility properties. The polymerized bitumen is coated onto a dimensionally stable reinforcement core of non-woven spun bond polyester rot-proof fabric. The membrane has excellent tensile & tear strengths and is highly resistant to puncture. It is flexible and is suitable for applications where high structural movement is expected.


  • Excellent resistance to positive water & vapor pressure
  • Good dimensional stability under tension
  • Excellent flexibility. Can accommodate high structural movements
  • High puncture and fatigue resistance
  • Excellent tensile and tear strengths
  • High resistance against water borne chemicals
  • Exhibits good low temperature flexibility with no physical strain

This TDS is applicable for the United Arab Emirates only. Please contact your local Polybit sales office for the available TDS in your region

Step by step

The application temperature should be between 5°C to 55°C. Application procedures may vary slightly depending upon site conditions. The general recommended guidelines for the application of the waterproofing system is as follows:


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/L 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.


Start the installation of all membrane plies from the low point or drains, so that the flow of water is over or parallel to the plies, but never against the laps. All overlaps at the membrane seams shall be installed so as to have "up" slope laps over "down" slope laps. Begin membrane application by unrolling the roll of BITUPLUS EX membrane and aligning the side laps. Re-roll the roll halfway and stand on the unrolled portion to prevent shifting. Side overlaps should be a minimum of 100 mm and the end overlaps 150mm.


BITUPLUS EX membrane is installed by using a cylinder fed propane gas torch. Use of hand-held 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 un-torched 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 the membrane being overlapped onto. Be sure to heat the entire roll evenly and not just the lap areas, with extra concentration at the laps.
Caution: Do not over torch the membrane as this will expose the reinforcement and cause damage to it.


Sealing Heat both the overlaps and use round tipped trowel to seal the overlap. Adequate heat is confirmed when a uniform flow of melted bitumen compound flows evenly in a bead that oozes from the applied membrane’s edges. Excess compound should be pressed into the seam using a heated trowel. Any un-bonded areas must be lifted and re-torched. Do not attempt to reseal by torching the top surface of the membrane. Protection BITUPLUS EX should be protected from getting damaged due to the ongoing site activities and during backfilling. Membranes laid on horizontal surfaces can be protected either by a cement sand screed (50mm thick) or by an asphaltic protection board (BITUBOARD)*. On vertical surfaces the membrane has to be protected with BITUBOARD. BITUBOARD can be fixed on the membrane by torching the underside of the board, or with a double sided bitumen adhesive tape (WATERTITE TS 15)*. Please contact our technical service team for specific requirement.