Description
Newton CDM 503 Membrane – BBA Certified Cavity Drain Membrane
Premium 3mm Waterproofing Membrane for Basements & Retaining Walls
The Newton CDM 503 Membrane is a BBA-certified (94/3010) cavity drain membrane designed for below-ground waterproofing in basements, cellars, retaining walls, tunnels, and vaulted soffits. As part of the Newton CDM System, this high-quality membrane provides a maintainable and highly effective Type C waterproofing solution.
With a 3mm stud profile, it is ideal for applications where space is limited, offering a fast installation process with minimal substrate preparation.
Key Benefits
✔ BBA Certified (94/3010) – Guaranteed 30-year lifespan, with an expected 50-year service life.
✔ Quick & Easy Installation – Requires minimal wall preparation for faster application.
✔ Highly Durable & Resistant – Rot-proof, resistant to root penetration, aggressive groundwater, salts, and hydrocarbons.
✔ Vapour Control & Humidity Management – Contributes to a Grade 3 internal environment as per BS 8102:2022.
✔ Space-Saving Design – 3mm stud depth ensures suitability for restricted spaces.
✔ Part of the Newton CDM System – Integrates with drainage & pumping solutions for complete waterproofing.
Typical Applications
✅ Basements & Cellars
✅ Vaulted Soffits & Retaining Walls
✅ Tunnels & Arches
✅ Damp-Proofing & Gas Control Applications
Product Data & Specifications
- Product Code: M5
- Roll Size: 20.0m x 2.0m (40m² coverage)
- Colour: White/Translucent
- Compressive Strength: 320 kPa
- Thermal Conductivity: 0.461 W/mK
- Water Vapour Resistance: >3020 MNs/g
- Fire Resistance: Euroclass E
- Chemical & Oxidation Resistance: 100%
Compliant with BS 8102:2022 – Structural Waterproofing Standards
The Newton CDM System fully complies with BS 8102:2022, ensuring maintainable, long-term waterproofing solutions. The British Standard recommends that a waterproofing specialist should be part of the project design team to ensure full system integration.
Recommendation: Installation should be carried out by a Newton Specialist Contractor (NSBC) for optimal performance.
Newton CDM System – Overview
The Newton Cavity Drain Membrane (CDM) System is a fully maintainable basement waterproofing solution, certified to BES 6001 by BRE Global. This system consists of:
✔ Cavity Drain Membranes & Drainage – Captures and redirects water ingress.
✔ Pumping & Control Systems – Works with Titan-Pro sump and Newton pumps for water removal.
✔ Gas Proofing – The Newton PAC-500 System integrates ground gas and waterproofing protection.
Associated products
CDM 503 Associated Products:
- Newton 800 Mesh Plugs - membrane fixings to walls above ground
- Newton Multiplugs - membrane fixings to walls below ground
- Newton 800 Cob Plugs - membrane fixings to walls above ground - poorer quality substrates such as cob walls
- Newton Waterseal Rope - plug sealing
- Newton Waterseal Tape - membrane joint sealing
- Newton 800 Mastic - an alternative to sealing with rope and tape
- Newton Overtape - floor and wall joint sealing
For further information please call our customer services team, 01268 472358.
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