Description
HydroTank 308 Stopaq – Flexible, Self-Sealing Pipe & Conduit Sealant
Advanced Pipe & Conduit Sealing for Waterproof & Gas-Tight Protection
The HydroTank 308 Stopaq is a single-component, permanently flexible sealing compound designed to effectively seal conduits, pipes, and service duct sleeves against water ingress and gas penetration.
This innovative non-curing compound remains flexible indefinitely, allowing for easy future modifications where additional services may need to be pushed through the existing seal. Upon contact with water, HydroTank 308 Stopaq swells by up to 10%, ensuring a tight, reliable seal even under 3m of water pressure.
No primers or special tools required – it adheres seamlessly to wet and dry surfaces, including concrete, mortar, and plastic, while maintaining flexibility without putting stress on joints or structures.
For a fully secure installation, finish with HydroTank 308 Stopaq Mortar, a fiber-reinforced, non-shrinking cap that allows for easy cable or conduit insertion without the need for power tools.
Key Benefits
✔ Fast & Easy Application – No special tools or curing time required.
✔ Permanently Flexible – Never hardens, allowing for future service modifications.
✔ Reusable & No Waste – Simply reapply as needed without material loss.
✔ Water & Gas Tight – Seals against running water leaks, radon, and vapours.
✔ Self-Sealing & Swellable – Expands up to 10% in water to reinforce the seal.
✔ No Fumes, No Chemical Reactions – Safe and environmentally friendly.
✔ High Adhesion – Bonds securely to wet and dry concrete, mortar, and plastic.
Typical Applications
✅ Sealing wall inlets below groundwater level – Prevents water and gas ingress in basements and earth-retained structures.
✅ Sealing running water leaks – Ideal for permanent waterproofing of pipe and cable penetrations.
✅ Gas-tight wall penetrations – Provides protection from flooding and ground gases.
✅ Multi-pipe & cable inlets – Perfect for horizontal wall penetrations with multiple conduits.
Product Data & Specifications
- Product Code: SX308-M
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Packaging:
- HydroTank 308 Stopaq: 0.53kg tubes (0.4L capacity)
- HydroTank 308 Stopaq Mortar: 0.5kg tubs (0.6L capacity)
- Colour: Green
Quick & Simple Installation
1️⃣ Prepare the Surface – Ensure the duct or service sleeve is clean and free from debris.
2️⃣ Apply HydroTank 308 Stopaq – Fill the space around the pipes or cables within the sleeve.
3️⃣ Let it Seal Naturally – The compound will self-seal and expand upon contact with water.
4️⃣ Finish with HydroTank Stopaq Mortar – Apply mortar for reinforced sealing and easy conduit modifications.
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Technical Data
| Features | Result |
| Material | Synthetic Polyolefin Compound |
| Colour | Green |
| Specific Gravity | 1.2 to 1.5 |
| Pack size – Cartridge | 0.4 Litres |
| Pot life | None |
| Shelf life | None |
| Moisture Absorption (ASTM D570) | 5 – 20% |
| Gap filling | 10 to 40mm |
| Flash Point | 170 |
| Installation Temperature | 5ºC to 35ºC |
| Service Temperature | -20ºC to +35ºC |
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