Bitumen Membrane Waterproofing in UAE

Bitumen based waterproofing membrane is produced with a mixture obtained by modifying high quality bitumen with elastomeric and elastomeric polymer additives

Bitumen based waterproofing membranes are used for waterproofing of undergroundconcrete surfaces, supporting walls, terraces, concrete roofs, wet floors. Torch or hot asphalt can be utilized in the applications of the membrane. SBS polymer-modified bitumen membranes commonly are installed in hot mopping of asphalt or cold adhesive. Some SBS modified membranes are self-adhering; that is, they contain an adhesive backing. APP polymer-modified bitumen membranes typically are heat-welded or torch-applied.

Procedure for Membrane Application

Horizontal Application

• One/Two layer of 4mm thick modified bituminous membrane shall be laid fully torched on binding concrete with minimum of 100mm end laps and 150mm side laps.
• The binding surface shall be primed with the primer recommended by manufacturer of the membrane prior to placing the membrane. Prior to succeeding works the applied primer shall be inspected by engineer 24hours after the placement.
• Waterproofing membrane installation shall be performed using cylinder fed propane gas torch, trowel to seal the seams of the membrane and knife for cutting.
• The membrane is then placed in the correct torching position, then re-rolled for about half of its length without changing its orientation.
• The membrane is then un- rolled again and torched on pressing the melted area against the substrate.
• Repeat till the entire length of membrane is bonded firmly onto the surface then the second membrane is laid in the same way with overlap of 150mm at the end of 100mm at the side.
• An extra length of minimum m of the horizontal membrane shall be left to carry up the verticalsurface to maintain continuity of the membrane and be protected.

Vertical Application

• One/two layers of 4mm thick modified bituminous waterproofing membrane shall be applied to all vertical surfaces of grunted shoring or blockworks wall.
• Before applying the waterproofing membrane, concrete surface shall be primed with primer recommended by manufacturer of the membrane but again it should be inspected by engineers 24 hours after the placement.
• The extra portion of 300mm of the horizontal membrane left shall be turned up and wrapped on to the vertical primed surfaces. The continuity of the membrane shall be maintained by minimum laps 150mm
• The membrane on the exposed external vertical surface shall be carried up to a minimum of 150mm above the finished ground level (.i.e. side wall, parapet etc.)and tucked into a continuous groove provided for the same ad secured firmly with approved sealant/ mastic recommended by the manufacturer of the membrane.
• The membrane fixed on the grunted or concrete wall shall be protected from any damage due to rebar fixing, formworks, concreting of raft, retaining wall works with approved type protection board fixed to the membrane.
• All areas of the membrane exposed above ground shall be protected with appropriate flashing.
• Inspection would be submitted for approval of engineers.
• Before fixing the steel reinforcement for foundation, the membrane shall be covered by one layer of geotextile and poured with 50mm thick layer of cement sand screed