Housing Society Waterproofing: Committee Evaluation & Tender Checklist

Cooperative housing society terrace inspection and tender evaluation protocol in Gujarat

1. Why Society Waterproofing Tenders Often Fail

Managing cooperative housing society repairs in Gujarat (Ahmedabad, Vadodara, Surat, Rajkot) is notoriously difficult. Common reasons projects encounter disputes or cost overruns include:

• Choosing the Lowest Bid Without Technical Scrutiny: Contractor A quotes ₹35 per sq. ft. using low-grade white slurry; Contractor B quotes ₹75 per sq. ft. using high-build PU elastomer with fiber mesh. Comparing only price results in choosing superficial solutions that fail within one monsoon.
• Vague Scope of Work: Contracts stating simply "waterproofing of terrace" without specifying surface grinding, crack routing, coving height, DFT thickness, or flood testing.
• Disputes Between Top-Floor and Lower-Floor Residents: Lower floor flat owners delaying approval because they do not feel the urgency of roof leaks.

2. Essential Pre-Tender Technical Checklist

Before inviting quotations or presenting to the General Body / AGM, the committee should require all bidding contractors to address these 5 items in writing:

1. Pre-Inspection Condition Survey: Does the contractor provide a written inspection report identifying specific defect zones (broken China mosaic, solar panel anchor points, parapet cracks, lift pit water ingress)?
2. Brand & Product Technical Datasheets: Require the exact manufacturer brand names (e.g. Dr. Fixit, Fosroc, Sika, Asian Paints SmartCare) and specify product grades rather than generic "chemical coating."
3. Number of Coats & Dry Film Thickness (DFT): The quotation must state the minimum wet/dry film thickness and required drying time between coats.
4. Mandatory 48-Hour Ponding Test: The contract must specify that the contractor will block terrace drainage spouts and fill the roof with 50mm of water for 48 hours. Final payment should be contingent on zero leaks observed by top-floor residents.
5. Written Warranty Specifics: Ensure the warranty document clearly defines whether both labor and replacement materials are covered if a leak recurs during the warranty period.

3. Milestone-Based Payment Structure

Protect society funds by structuring payment terms tied strictly to verified milestones:

• Advance upon mobilization: 15% to 20% (for material procurement on site).
• Upon surface preparation & crack routing: 25%.
• Upon completion of primary waterproof coats: 30%.
• Upon successful 48-hour flood ponding test: 20%.
• Retention money (released after 1 full monsoon season): 5% to 10%.