Class B Breather Membrane
Why Partel EXOPERM DURO 300 Fuse?
EXOPERM DURO 300 Fuse is a high strength, diffusion permeable breather membrane designed to provide durable weather protection for the building envelope. It has a Reaction to Fire classification of B-s1, d0 and is suitable for demanding façade and roof applications.
- B-s1,d0 Reaction to Fire classification
- Triple layer fused construction for enhanced strength and stability
- Highly vapour open with an Sd value of 0.12 m
- Class W1 resistance to water penetration before and after ageing
- High tensile strength for demanding façade and roof applications
- High tear and nail tear resistance for exposed site conditions
- UV resistant for temporary exposure before cladding installation
- Temperature resistant from −40 °C to +80 °C
- Weather tight and wind resistant
- Suitable for walls and roofs with temporary exposure
- Improves durability of the building envelope
- Independently tested to EN standards for performance compliance
Technical Data
| WEIGHT | EN 1849-2 | 300 g/m² ±5% |
| REACTION TO FIRE | EN 13501-1 | B-s1,d0 |
| Sd VALUE | EN ISO 12572 | 0.12 m |
| WATER RESISTANCE | EN 1928 | W1 |
| TENSILE STRENGTH MD / CD | EN 12311-1 | 340 / 240 N / 5 cm (before ageing) 320 / 220 N / 5 cm (after ageing) |
| NAIL TEAR RESISTANCE MD / CD | EN 12310-1 | 220 / 240 N |
Application
EXOPERM DURO 300 Fuse is an external breather membrane designed for use on the cold side of insulation on façade wall and roof applications, providing durable weather protection and vapour permeability for the building envelope.
Suitable for:
- Facades with open or closed joints
- Roof applications
- Ventilated façade systems
- Commercial and residential developments
- Timber and steel framed constructions
- Offsite construction
- New builds and retrofits
- Projects requiring temporary exposure before cladding installation
Triple Layer Fuse Technology
EXOPERM DURO 300 Fuse is a breathable triple layer membrane with a fused functional layer designed for strength, dimensional stability and long term durability.
The fused layer provides enhanced protection for the building envelope:
- Transports vapour to outside
- Maintains high waterproof performance
- Creates a continuous wind tight and weather resistant membrane
- Protects insulation from wind washing
- Provides high resistance to tearing and mechanical damage
- Ensures reliable performance during temporary exposure
Unlike standard membranes, the fused construction provides improved durability and stability, making it suitable for façades, roofs, modular construction and retrofit projects where membranes may remain exposed before final cladding is installed.
Dimensions
- 1.5m X 30m = 45m² (59-1/16” X 98’-5-1/8” = 485 SF)


