The aim of this Method Statement is to provide and maintain effective quality control procedures and to execute the work in compliance to standard and good practice at all stages and activities for Cementitious and Reactive Waterproofing for Floor and Walls of Evaporator pits, Electrical Cable Trenches, Sump Pits and other locations as shown on the drawings.
Following equipment’s and tools will be used as required during Cementitious Waterproofing.
- Wire Brushes (for cleaning)
- Soft Brushes (for cleaning)
- Air Compressor
- Paint Brushes (for application)
- Paint rollers (for application)
- Hand Trowel
- Spatula
- Slow speed heavy duty Drill
- Mixing Paddle
- Spraying Machine and Nozzles (optional)
- Other Hand Tools etc.
STORAGE AND HANDLING OF WATERPROOFING MATERIALS
- Materials shall be stored in a cool and dry place and avoid putting in direct sun light and as directed by the materials manufacturer.
- Materials shall be placed in a way to avoid the direct contact with ground soil.
- Materials shall not be exposed to the fire or naked flames in any circumstances.
- Material Safety Data Sheet (MSDS) shall be followed for safety and handling recommendations.
- The materials damaged during transportation, handling or storing shall not be used at site.
- Adequate protection against damage to the waterproofing system shall be provided where further construction work is necessary in the area.
Surface Preparation for Cementitious Waterproofing
- Surface / substrate preparation is the most important for Cementitious and Reactive Waterproofing System.
- The concrete surface / substrate shall be clean and free from contamination such as dust, oil, grease, organic growth and release agents etc.
- The surface shall be free from standing water.
- All loosely adhering particles such as mortar and cement laitance shall be removed.
- The surface would be cleaned by brushing and finally soft brushing or compressed air.
- Cracks (if any) shall be routed out as recommended by the manufacturer.
- The substrate condition shall be approved by the consultant prior to start application.
- Verify that concrete cants are provided at locations where topping abuts vertical surface.
- Chip out concrete around sleeves, anchors, inserts and other items projecting from concrete.
APPLICATION OF FOSROC Nitocote CM210 ELASTOMERIC CEMENTITIOUS COATING
Mixing
- Separate buckets shall be used for measuring and mixing the materials.
- The temperature of mixing water shall be as directed by the waterproofing manufacturer.
- Only sufficient quantity shall be mixed that can be applied within time recommended by manufacturer.
- Slow speed drill fitted with a mixing paddle shall be used for mixing.
Waterproofing Material Application
- Substrate surface shall be thoroughly wetted/dampen.
- The mixed material shall be used by brush, trowel or roller as per site condition and finishing requirements.
- For spray application the substrate shall be prepared in the same manner as of brush application.
- The material shall be applied in two coats.
- Each coat should be a minimum of 1 mm thickness.
- Allow a minimum of 5 hours cure at 20 and 3 hours at 35 between the first and second coats.
- The application of waterproofing shall be done under competent personnel’s supervision and as per manufacturer’s recommendations.
Curing of Cementitious Waterproofing Works
Manufacturer’s printed recommendations shall be followed for curing the waterproofing.
A wet sponge or light pressure spray method shall be adopted for curing.
Curing shall be started after hardening 2nd coat of application.
Allow a minimum cure time of equivalent to 3 days at 20 and above with potable water.
Inspection and Testing
Prior to concealing the waterproofing membrane, IR shall be raised for approval of cementitious waterproofing works.
All subsequent works after cementitious waterproofing shall be carried out only after getting written approval from client / consultant.