Product Manuals
1. Introduction to HDPE Technology
High Density Polyethylene (HDPE) sheet membranes are pre-applied, fully bonded waterproofing systems. Installed above PCC, they bond integrally with fresh RCC, preventing any lateral migration of water even if punctured.
Two main variants:
- Sanded HDPE → mechanical grip with fresh concrete.
- Bonded HDPE → pressure-sensitive adhesive polymer ensures adhesion.
Widely adopted for deep basements, high water table sites, and aggressive soils.
2. Advantages
- Fully bonded → no lateral water migration.
- Excellent chemical resistance (salts, sulfates, chlorides).
- Works even on damp PCC (no dry surface required).
- Long service life (>10 years).
- Suitable for both horizontal rafts and vertical walls.
3. Limitations
- Requires trained applicators for overlap and terminations.
- Deep basements excessive sludge can disturb the bonding adhesion with concrete
- Can be damaged during rebar fixing or concreting.
- Bonded membranes move & deflect with the structural movements
- Terminations must be strictly as per detail drawings.
4. Performance Parameters
Property | Requirement | Standard |
Thickness | ≥ 1.2 mm | Manufacturer spec |
Elongation | ≥ 300% | ASTM D412 |
Tensile Strength | ≥ 25 MPa | ASTM D412 |
Peel Adhesion to Concrete | ≥ 750 N/m | ASTM D903 |
Puncture Resistance | ≥ 900 N | ASTM F1306 |
Hydrostatic Pressure Resistance | ≥ 60 m | ASTM D5385 |
5. Recommended Use Cases
- Deep basements with high hydrostatic pressure.
- Rafts with damp PCC or aggressive soil conditions.
- Retaining walls (confined and unconfined).
- Projects requiring 10+ years guaranteed waterproofing.
6. Application Steps
Surface Preparation
- PCC free of laitance, sharp edges, and standing water.
- Honeycombs voids repaired with same-grade concrete.
Membrane Laying
- Place with non-adhesive side facing PCC, adhesive/sanded side up.
- Overlaps: 70–80 mm, staggered.
- Selvage overlaps sealed with pressure-sensitive adhesive tape.
- In damp conditions, warm overlap with hot air gun before sealing.
- Keep ≥500 mm clearance from reinforcement.
Termination
- Unconfined walls: terminate 40 mm below raft top.
- Confined walls: extend 300–500 mm above raft, fixed to shuttering, with flashing.
Inspection & Repairs
- Inspect for punctures, scratches, overlap gaps.
- Small scratches: pressure-sensitive tape.
- Punctures: patch with ≥150 mm overlap sheet.
- Record repairs on as-built drawings.
Concreting
- Concrete placement only after inspection approval.
- Remove shuttering after RCC reaches ≥20 N/mm².
7. Section Drawings
- Raft + retaining wall junction with HDPE.
- Termination detail (confined/unconfined).
8. Inspection Test Plan (ITP)
- One test per site if <1000 m²; thereafter one per 1000 m².
- Random sampling allowed by client/third party.
- Samples from centre + 1m from edges.
- Tests: thickness, elongation, tensile, peel adhesion, puncture, hydrostatic resistance.
9. Documents
Specifications, BOQ, and Checklist
10. General Specification Clause
“S12121212”
10. Reference Standards
- ASTM D412 – Tensile Properties
- ASTM D903 – Peel Adhesion
- ASTM F1306 – Puncture Resistance
- ASTM D5385 – Hydrostatic Pressure Resistance
- IS 2645 – Integral Waterproofing Admixtures
- ACI 350 – Environmental Engineering Concrete Structures
5. Video Masterclass
SpecX Masterclass: HDPE Membrane Waterproofing — Coming Soon
Disclaimer
SpecX is an industry initiative & a neutral resource, compiled from industry references and best practices. It is not brand-specific. Always cross-check with project requirements and local codes before finalizing specifications.