Lot-1: Construction of Treatment Plant Building and Civil Works for Water Supply System
Technical Specifications
6 WATER PROOFING
6.1
General
The principal work of this Section includes, but may not be limited to:
a. Application of waterproof membrane to all portions below ground and up to
300 mm above grade of tanks and structures and roofs, floors of wet rooms
like toilets, kitchens etc.
b. application of waterproofing to floors, walls and soffits of water tanks and
reservoirs (internal faces), walls of wet rooms, walls of planters, etc.,
c. Protective painting of concrete foundation and sunken courts in contact with
soil.
6.2
Materials
Products and manufacturers specified hereinafter are specified for establishing minimum
quality standards. Products equal in quality to, or better than those specified, will be
considered acceptable but the decision of acceptability rests with the Employers
Representative.
6.2.1
Waterproof Sheet Membrane
A. Waterproofing membranes and associated materials shall be sourced and supplied
by a single manufacturer with a minimum of ten years experience. The manufacturer
shall operate a Quality System which is registered to ISO 9001
B. The waterproof membrane sheeting shall be impervious, cold applied flexible
laminated sheet consisting of multi-layer, high-density, cross-laminated, polyethylene
film with a backing of self-adhesive rubber bitumen compound, a combined thickness
of 1.5 mm and protected with silicone coated release paper. A special grade of
compound formulated for hot and wet climates must be used. The total weight shall
be not less than 1.6 kg/sq.m gross. The membrane shall be supplied in roll form not
less than 20 metres long, not less than one metre wide, wound on a rigid tube and
shall, in all respects, comply with the requirements of British Code of Practice CP 102
and BS 8102.
C. Performance and testing of characteristics shall be as follows:
Property
Test Method
Typical Results
Tensile strength at ASTM D638
break - film
Long 42 N/mm2
Trans 51 N/mm2
Tensile strength at ASTM D638
break - membrane
Long 4.2 N/mm2
Trans 5.1 N/mm2
Elongation at break ASTM D638
- film
Elongation at break ASTM D638
- compound
Tear strength - film ASTM D1004
UNOPS- MVPC
Long 230%, Trans 180%
Trans 1250%
Long 380 N/mm
Trans 360 N/mm
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Lot-1: Construction of Treatment Plant Building and Civil Works for Water Supply System
Technical Specifications
Tear strength
membrane
- ASTM D1004
Long 30 N
Trans 30 N
Adhesion to primed
concrete
Adhesion to self
Puncture
resistance
of
membrane
Water absorption after 24 hours
Water absorption after 35 days
Environmental
resistance
Water
vapour
transmission rate
at 25oC, 75 % RH
ASTM D1000
2.0 N/mm
ASTM D1000
ASTM E154
4.0 N/mm
230 N 53 mm
ASTM D570
0.13% by weight
1.0 % by weight
ASTM D543
Conforms
ASTM E96
0.3 g/m2/24 hours
at 35oC, 90 % RH
1.0 g/m2/24 hours
Adhesive softening ASTM D36
point
110 oC
D. Preformed asphalt board, composed of aggregate bonded in bitumen and encased
between two layers of asphaltic felt shall be supplied as 3 mm thick boards 1.829
metres x 0.914 metres (1.67 m2) weighing approximately 6.5 kg. The boards shall be
spot bonded into position with high quality solvent borne contact adhesive based on
polychloroprene rubber specially formulated for hot climates to give a minimum
coverage of 10 to 12 m2 per litre of spot bonded area.
E. Prior to the application of the waterproof membrane to vertical and horizontal
surfaces (except horizontal blinding), the concrete will be primed with one brush coat
of compatible primer containing 50% aromatic hydrocarbon solvents and 50%
bitumen solids to give an average coverage of approximately 10 to 12 sq. metres per
litre, dependent on texture and porosity of concrete surface. The primer shall be
compatible with the waterproofing membrane and recommended by waterproofing
membrane manufacturer.
F. Preformed triangular fillet shall be black triangular PVC extrusion with a wall
thickness of 5 mm, 40 mm x 40 mm coated on two faces adjacent to rounded corner
with grey self-adhesive compound protected by silicone coated release paper. The
angle fillet shall be provided between slabs and up stands.
G. Bituminous mastic shall be cold applied gun grade rubber/bitumen mastic compound,
for moulding into fillets, collars and tapes for sealing around pipes and irregularities.
H. Where polyethylene sheeting is laid under slabs and floors it shall be turned up and
jointed to the membrane as recommended by the specialist manufacturer.
6.3
Surface preparation, Storage of materials, Application
Surface preparation, storage of materials application and curing shall be strictly as per the
manufacturers specification.
UNOPS- MVPC
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