Protective paint POSEIDON

coatingsprayliquid

Product Overview
Poseidon Bathroom & Wetroom Waterproofing Membrane Paint is a liquid-applied, polymer-based membrane available in 7kg, 10kg and 12kg containers. Designed for spray, roller or brush application, it provides a seamless, flexible and durable waterproofing layer suitable for high-moisture environments. The formulation creates a long-lasting vapour barrier that protects wet areas from water ingress and vapour penetration and accommodates building movement without cracking, ensuring waterproof performance in bathrooms, steam rooms and wetrooms prior to tiling.

Materials and Composition
The Poseidon membrane is a polymer-based, liquid-applied coating that cures into a continuous flexible film. It is engineered for durability and resistance to water vapour transmission, with adhesion tailored to substrates such as concrete, cementitious bases and tiles. The cured membrane is resistant to UV exposure, chemicals and environmental wear and is suitable for continuous contact with moisture and steam when used as specified.

Dimensions and Coverage
The product is supplied in 7kg, 10kg and 12kg containers. Coverage depends on application thickness; as a guide a 10kg container typically covers approximately 15–20 m² at a 1 mm thickness. The recommended minimum thickness for effective waterproofing is 1 mm. Coverage will vary with substrate porosity and application method.

Key Features

• High Vapour Barrier Performance – Provides a complete vapour block to prevent moisture transmission in wet areas.
• Seamless and Flexible – Cures into a continuous membrane that accommodates substrate movement without cracking.
• Easy Application Options – Suitable for spray, roller or brush application for rapid installation.
• Durable Long-Term Waterproofing – Offers reliable protection against water ingress and vapour penetration for years when correctly applied.
• Adhesive Compatibility – Bonds effectively to concrete, cement-based substrates and tiles to ensure a secure waterproof installation.

Ideal Use Cases
Designed for professionals and competent DIYers working on bathrooms, wetrooms, steam rooms, showers and other high-moisture areas. Suitable for new installations and refurbishments where moisture control and long-term waterproofing are required. Ideal when quick project turnaround and minimal downtime are priorities.

Application & Key Details

• Application methods: Airless spray machine, roller or paintbrush (spray/roller/brush).
• Drying/curing: Allow to dry undisturbed; keep free from water contact until fully cured.
• Cleanup: Tools and equipment can be cleaned with cold water after use.
• Protection: Once cured, the membrane is robust and should be protected until tiling or finishing layers are applied.
• Ventilation: Ensure good airflow during application, especially in high-humidity areas.
• Not suitable for: Bitumen/asphalt-based substrates, continuous standing water pressure, moving cracks or highly flexible joints and incompatible existing coatings unless prepared.

Suitable Substrates

• Concrete and concrete blocks
• Brickwork
• Cement-based plaster
• Water-resistant plasterboards
• Existing tile floors and walls (prepared)
• OSB, plywood, chipboard (substrate preparation/priming as required)
• Gypsum moisture board and other wetroom-specific substrates (use appropriate primer where indicated)

Included Items & Storage
Each order includes the selected volume of Poseidon membrane in a ready-to-use container. No application tools are included; rollers, brushes or spraying equipment are recommended. Store in a cool, dry place away from direct sunlight, tightly sealed to avoid contamination. Avoid exposure to extreme temperatures and prolonged UV prior to application.

Care & Maintenance
After curing the membrane requires no special maintenance. Clean with water and mild detergents if necessary. With correct application and handling the membrane offers long-term waterproof protection.

Tested & Certified

• European Technical Assessment ETA-23/0378 (CE) — 25-year assessed working life.
• EN 14891 — Watertight & crack-bridging (no water penetration; 0.4 mm crack-bridging; watertight through 2 mm joint movement).
• Tile-adhesive bond retained after water, heat & chlorinated (pool/spa) water — EN 14891.
• ANSI ANSI A118.10 (waterproof) & A118.12 crack isolation (High Performance); zero-VOC emissions (CA 01350).
• Adhesion Strength — Strong adhesion to brick, block, screed, tile & gypsum (1.0–1.6 N/mm², EN ISO 4624) · EPD (EN 15804).

World Market Compliance
Tested to both US ASTM standards and European EN standards so the same membrane can be specified for projects in the UK, Europe and North America.

Related Guides & Documentation (titles only)

• NHBC Standards 2023: Waterproof Membranes as a Tanking System
• Five Things About Waterproofing
• Damp Proofing vs Waterproofing: What is the Difference?

Technical characteristics / specifications

• Product collection: Poseidon
• Applied by: Airless spray machine, roller or paintbrush
• Colour: Blue
• Available sizes: 7kg, 10kg, 12kg
• Typical coverage: ~15–20 m² per 10kg at 1 mm thickness (dependent on substrate and application)
• Recommended minimum thickness: 1 mm
• Suitable for: Bathrooms, wetrooms, showers, kitchens and areas with regular water exposure
• Adheres to: concrete, brick, cement-based plaster, existing tiles, OSB/plywood/chipboard (substrate prep/primers may be required)
• VOC: zero-VOC emissions (CA 01350) for specified tests
• Certifications: ETA-23/0378, EN 14891, ANSI A118.10, A118.12, EPD (EN 15804)
• Typical adhesion: 1.0–1.6 N/mm² (EN ISO 4624)
• Crack-bridging: 0.4 mm (EN 14891); watertight with joint movement up to 2 mm