wedi Building Board Vapor – Waterproof XPS board with additional vapour barrier layer
The wedi Building Board Vapor is specifically designed for environments with permanently high humidity levels. Thanks to its integrated vapour-retardant epoxy resin layer (sd-value approx. 283 m), the board withstands extreme condensation and continuous moisture exposure. Ideal for professional wellness facilities, steam rooms, public showers and other high-demand wet areas.
➕ Additional vapour-retardant layer for extreme moisture loads
➕ 100% waterproof, thermally insulating and dimensionally stable
➕ Ready to tile thanks to the glass fibre reinforced cement coating
➕ Lightweight and easy to process
➕ Perfect for wellness, steam rooms, sports facilities and public showers
Technical specifications
- Material: extruded polystyrene (XPS) with cement coating
- Vapour barrier: 1.5 mm epoxy resin layer (sd-value approx. 283 m)
- Dimensions: 2500 x 600 mm
- Thicknesses: 12.5 mm, 20 mm, 50 mm (excluding 1.5 mm vapour layer)
- Applications: saunas, steam rooms, swimming facilities, wellness spaces, public showers
- Thermal conductivity: approx. 0.036 W/mK
- Water absorption: 0% – fully waterproof
- Fire classification: E (EN 13501-1)
Applications with wedi Vapor
wedi Vapor is ideal for continuously wet environments such as steam rooms, wellness spaces, treatment rooms, sports facilities and heavily used communal shower areas. The board prevents vapour penetration and provides long-lasting, safe and waterproof construction performance.
wedi Building Board Vapor – the professional solution for extreme humidity and vapour load
The wedi Building Board Vapor is engineered for environments exposed to permanent moisture, condensation and intensive steam generation. Equipped with a 1.5 mm epoxy resin vapour barrier (sd approx. 283 m), it offers outstanding protection against vapour diffusion and ensures that the structure behind the board remains dry and safe. This makes it the ideal choice for steam rooms, spa and wellness facilities, swimming areas and other high-demand commercial wet zones.
Maximum protection against vapour diffusion and condensation
While standard XPS building boards are fully waterproof, the Vapor version provides an additional layer of protection. The integrated epoxy barrier prevents vapour transmission even under extreme temperature and humidity conditions. This avoids moisture damage, mould growth and structural deterioration.
Designed for professional spa, wellness and steam room projects
The Vapor board meets the strict requirements of commercial wet environments. It resists continuous moisture, high temperatures and condensation exposure while providing a safe and stable substrate for tile or natural stone finishes. Even under heavy use, the construction remains durable and hygienic.
Advantages of the Vapor building board
➕ Extremely strong vapour barrier (sd approx. 283 m)
➕ 100% waterproof XPS core – suitable for demanding wet rooms
➕ High dimensional stability and thermal insulation
➕ Ready to tile thanks to reinforced cement coating
➕ Lightweight and easy to install
➕ Ideal for steam rooms, spas, sports facilities and public showers
Fast and reliable installation with wedi Tools
The Vapor board is installed in the same way as standard wedi building boards. It can be cut, shaped and bonded easily. wedi 610 provides a long-lasting waterproof bond, while wedi sealing tapes ensure vapour-tight and waterproof joints.
- wedi 610 – adhesive and sealant for strong waterproof bonds
- wedi Joint Reinforcement Tape – ideal for material transitions
- wedi Sealing Tape – for fully waterproof joints
- wedi Rosettes & Plugs – for mechanical fixing if required
Applications of the Vapor board
Common applications include:
- steam rooms and hammams
- professional spa and wellness facilities
- public and commercial shower areas
- swimming and aquatic centres
- treatment rooms and therapy spaces
- sports and fitness facilities
Technical specifications
| Manufacturer | wedi |
| Product name | wedi Building Board Vapor |
| Type | XPS building board with integrated epoxy vapour barrier |
| Dimensions | 2500 x 600 mm |
| Thicknesses | 12.5 mm, 20 mm, 50 mm (plus 1.5 mm barrier layer) |
| Vapour resistance | sd-value approx. 283 m |
| Thermal conductivity | approx. 0.036 W/mK |
| Water absorption | 0% – fully waterproof |
| Fire classification | E (EN 13501-1) |
| Suitable for | tiles, cement-based render, natural stone |
Part of the professional wedi system
The Vapor board is an essential component of the wedi system, offering superior safety where standard building boards are insufficient. Combined with wedi Fundo shower elements, wedi Top surfaces, niches and benches, it forms a long-lasting, hygienic and vapour-tight construction system for demanding wellness and spa projects.
