Lot-1: Construction of Treatment Plant Building and Civil Works for Water Supply System

Technical Specifications

UNOPS- MVPC 22

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 Employer‟s

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

break - film

ASTM D638 Long 42 N/mm2

Trans 51 N/mm2

Tensile strength at break - membrane

ASTM D638 Long 4.2 N/mm2

Trans 5.1 N/mm2

Elongation at break - film

ASTM D638 Long 230%, Trans 180%

Elongation at break - compound

ASTM D638 Trans 1250%

Tear strength - film ASTM D1004 Long 380 N/mm

Trans 360 N/mm

Lot-1: Construction of Treatment Plant Building and Civil Works for Water Supply System

Technical Specifications

UNOPS- MVPC 23

Tear strength - membrane

ASTM D1004 Long 30 N

Trans 30 N

Adhesion to primed concrete

ASTM D1000 2.0 N/mm

Adhesion to self ASTM D1000 4.0 N/mm

Puncture resistance of membrane

ASTM E154 230 N 53 mm

Water absorption - after 24 hours

ASTM D570 0.13% by weight

Water absorption - after 35 days

1.0 % by weight

Environmental resistance

ASTM D543 Conforms

Water vapour transmission rate

ASTM E96

at 25oC, 75 % RH 0.3 g/m2/24 hours

at 35oC, 90 % RH 1.0 g/m2/24 hours

Adhesive softening point

ASTM D36 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

manufacturer‟s specification.