1. Scope of Work

This method statement describes the procedures for waterproofing application in civil buildings, including roofs, balconies, bathrooms, kitchens, podium decks, and underground structures.

The waterproofing system may include:

• Liquid-applied waterproofing membrane (PU / acrylic / cementitious)
• Bituminous membrane system
• Protective screed or finishing layer

All works shall be carried out in accordance with approved drawings, specifications, and manufacturer’s recommendations.

2. Materials

• Waterproofing membrane (PU / cement-based / bituminous sheet, as specified)
• Primer (compatible with substrate)
• Reinforcement fabric (polyester mesh, if required)
• Sealant for joints and penetrations
• Protection board or cement screed
• Tile adhesive (for wet areas)

All materials must be approved before application.

3. Surface Preparation

• Substrate must be structurally sound, clean, dry, and free from dust, oil, grease, loose particles, or laitance.
• Repair cracks, honeycombs, and uneven surfaces using suitable repair mortar.
• Ensure adequate slope toward floor drains (minimum 1–2%).
• Remove standing water before application.
• Apply primer uniformly and allow it to dry before membrane application.

4. Application Procedure

4.1 Roof / Balcony Areas (Liquid Membrane System)

1. Apply first coat of waterproofing membrane using roller or brush.
2. Embed reinforcement mesh at corners, joints, and around penetrations.
3. Apply second coat perpendicular to the first coat after curing.
4. Total dry film thickness shall comply with specification (typically 1.5–2.0 mm).
5. Allow proper curing before applying protection layer.

4.2 Bathroom / Wet Areas (Cementitious Waterproofing)

1. Apply first coat uniformly on floor and wall upturn (minimum 300 mm height).
2. Reinforce floor-wall junctions and pipe penetrations.
3. Apply second coat after initial curing.
4. Conduct flood test (24–48 hours) before tiling works.

4.3 Bituminous Membrane System (If Applicable)

1. Apply primer and allow to dry.
2. Torch-apply membrane with proper overlap (minimum 80–100 mm).
3. Ensure full adhesion without air pockets.
4. Seal all overlaps and terminations properly.

5. Detail Treatment

• Apply additional reinforcement at:
  • Internal and external corners
  • Construction joints
  • Pipe penetrations
  • Drain outlets
• Ensure all terminations are sealed with approved sealant.
• Provide upturns at parapets and vertical surfaces as specified.

6. Inspection and Testing

• Visual inspection for uniform thickness and coverage.
• Thickness measurement (if required).
• Flood test for wet areas and balconies (24–48 hours).
• Repair any leakage before proceeding with finishing works.

7. Protection and Finishing

• Apply protection screed or protection board after curing.
• Prevent damage during subsequent construction works.
• Do not allow heavy traffic before protection layer is completed.

8. Safety Measures

• Workers must wear appropriate PPE.
• Ensure proper ventilation in enclosed areas.
• Follow fire safety measures when using torch-applied membranes.