Newton Hydrobond 403 – Self-Healing Type A Waterproofing Membrane - 20m2
Newton Hydrobond 403 is a high-performance, self-healing waterproofing membrane designed for the external waterproofing of below-ground structures, including basements, foundation rafts, earth-retained walls and civil engineering applications.
Hydrobond 403 is a Type A (barrier) waterproofing membrane that forms a full mechanical bond with concrete. When installed above foundation slabs or against formwork, the membrane’s locking fleece becomes encapsulated within the concrete pour, preventing lateral water migration between the membrane and the structure.
A unique hydrophilic polymer layer enables the membrane to self-seal around minor penetrations or fixings, maintaining waterproof integrity even if the membrane is locally damaged during installation.
Hydrobond 403 forms part of the Newton Hydrobond System and is supported by BDA Agrément certification and NHBC acceptance, making it suitable for waterproofing designs to BS 8102:2022 (Grades 1, 2 and 3).
Key Benefits
Self-healing waterproofing membrane with hydrophilic polymer technology
Full mechanical bond to concrete prevents water tracking
Type A barrier protection for below-ground structures
Excellent flexibility and crack-bridging performance
Automatically seals small punctures on contact with water
Suitable for domestic, commercial and civil engineering use
Compatible with the Newton HydroBond waterproofing system
BDA Agrément certified and NHBC accepted
Optional gas-barrier variants available
Typical Applications
External waterproofing of basements and foundation rafts
Earth-retained reinforced concrete walls
Waterproofing beneath slabs and below-ground structures
Civil engineering structures requiring barrier waterproofing
Projects designed in accordance with BS 8102:2022
Integrated waterproofing systems using pre- and post-applied membranes
Performance & Compatibility
HydroBond 403 sits within the Newton HydroBond System of Type A barrier solutions and can be tied into other membranes (such as HydroBond 402 & HydroBond 401 SA) for complete site waterproofing and, if required, radon/ground gas protection (please contact us if you need these specialist membranes)
Technical Data – Newton HydroBond 403
| Property | Specification |
|---|---|
| Product Type | Self-healing externally applied waterproofing membrane |
| Waterproofing Classification | Type A (Barrier Protection) |
| System | Newton HydroBond Waterproofing System |
| Membrane Construction | Composite sheet with locking fleece and hydrophilic polymer coating |
| Bonding Method | Full mechanical bond via concrete encapsulation |
| Self-Healing Capability | Hydrophilic polymer expands to seal minor punctures |
| Thickness | Approx. 1.2 mm |
| Roll Width | 1.0 m |
| Roll Length | 20 m |
| Roll Coverage | 20 m² per roll |
| Flexibility | Excellent crack-bridging and movement accommodation |
| Water Resistance | Fully impermeable to liquid water |
| Chemical Resistance | Resistant to groundwater salts and contaminants |
| Installation Method | Pre-applied to substrate or formwork prior to concrete pour |
| Use Location | External, below-ground structures |
| Compliance | Designed to comply with BS 8102:2022 |
| Certifications | BDA Agrément; NHBC acceptance |
| Variants Available | Standard and gas-barrier versions (e.g. 403 GB) |
| Expected Design Life | In line with building life (≈60 years) |
Frequently Asked Questions
What is Newton HydroBond 403 used for?
HydroBond 403 is used for external waterproofing of below-ground structures such as basements and foundations, providing Type A barrier protection.
How does the self-healing feature work?
If the membrane is punctured, the hydrophilic polymer layer expands when in contact with water, sealing small holes and maintaining waterproof integrity.
What does mechanical bonding mean?
The membrane’s locking fleece becomes embedded in the concrete during pouring, forming a physical bond that prevents water tracking between the membrane and the structure.
Can HydroBond 403 be used with other Newton products?
Yes. It integrates with other HydroBond membranes, accessories and drainage components to form a complete waterproofing system.
Is HydroBond 403 suitable for NHBC-regulated projects?
Yes. It is supported by BDA Agrément certification and accepted by NHBC for Type A waterproofing to BS 8102:2022.
Newton Hydrobond 403 Waterproofing Membrane – 20m2
Returns accepted within 14 days and only with original packaging.

















