Selecting waterstop tape for a specific construction project requires understanding several key factors: joint types, expected water pressure, concreting method and specific site conditions. The wrong choice can compromise the entire waterproofing system and lead to costly repairs after the structure is commissioned.
As a PVC waterstop manufacturer with over 30 years' experience, at Plast Commerce we consult designers and builders daily on making the right choice. In this article we walk you through the entire decision-making process — from project analysis to specific specification.
Step 1: Analyse Your Project
Before selecting a specific waterstop type, you need to answer four fundamental questions. Each directly affects the tape specification:
What types of joints are in the structure?
Construction joints (concreting breaks) require strips without compensator (Type A, AE). Expansion joints (designed for movement) require strips with compensator (Type D, DE). Most projects have both types.
What is the expected water pressure?
Water pressure determines the required strip width. For foundations with low groundwater (up to 0.3 bar), 150–200 mm is sufficient. For treatment plants and reservoirs (0.5–0.7 bar) — 200–240 mm. For dams and deep structures (over 1 bar) — 240–320 mm.
What is the access to the joint?
If you have access to the middle of the concrete section, centre placement (Types A, D) is more reliable. If access is limited, use external placement (Types AE, DE).
What is the chemical environment?
PVC strips are resistant to most chemicals encountered in construction, including the alkaline environment of concrete. For aggressive environments (industrial wastewater, chemical reservoirs), consult our technical team for the appropriate material composition.
Recommendations by Project Type
Each construction type has its specific requirements. Below are our standard recommendations, based on decades of production experience and consulting on construction projects:
Foundations and Basements
Predominantly construction joints, moderate water pressure from groundwater
Water Reservoirs
Permanent water contact, high watertightness requirement
Water Treatment Plants
Chemical resistance, permanent water contact, expansion joints
Tunnels and Channels
High pressures, long structures with multiple expansion joints
Underground Car Parks
Combination of construction and expansion joints over large areas
Dam Walls
Maximum hydrostatic pressure, critical waterproofing
Important
These recommendations are indicative. The specific specification should always be determined by the structural designer based on the hydrogeological report, loads and the design watertightness class. Contact us for free consultation on your specific project.
Selection Summary Table
| Factor | Construction Joint | Expansion Joint | Note |
|---|---|---|---|
| Joint type | Type A or AE | Type D or DE | Primary selection criterion |
| Access to joint | Centre (A) when accessible | External (DE) when access is limited | Determines placement method |
| Water pressure up to 0.5 bar | 200 mm width | 200 mm width | Standard structures |
| Water pressure 0.5–2.5 bar | 240–320 mm width | 240–320 mm width | Deep structures |
5 Common Waterstop Selection Mistakes
1. Strip without compensator on an expansion joint
The most common and dangerous mistake. When the joint moves, a strip without compensator tears, completely compromising the waterproofing. Solution: Always check project documentation for joint types. If the joint is an expansion joint — use only Type D or DE.
2. Strip too narrow for the water pressure
A narrower strip is cheaper but at high water pressure it doesn't provide sufficient water path and may leak. Solution: Follow the width-to-pressure table. Investing in a wider strip is negligible compared to the cost of repair.
3. Incorrect orientation during external placement
External placement strips (AE, DE) have an asymmetric profile and must be installed on the water pressure side. A reversed strip doesn't function correctly. Solution: Mark the water pressure side and verify orientation before concreting.
4. Poor weld connections
Connections between strip sections are the most vulnerable points. Cold or overheated welds, insufficient overlap and dirty surfaces lead to leaks. Solution: Train staff in thermal welding and ensure a minimum 50 mm overlap.
5. Strip damage during concreting
Vibrating directly on the strip or uncontrolled concrete pouring can displace or damage the strip. Solution: Fix the strip securely, vibrate on both sides of it, and pour concrete evenly.
How to Order from Plast Commerce
Submit an enquiry
Describe the project: construction type, joint dimensions, expected water pressure, required quantity in linear metres.
Receive consultation
Our technical team will review your requirements and recommend the appropriate type, width and accessories.
Production and delivery
Standard sizes are in stock. For non-standard specifications — production within 20 working days.