173 Alfa Rufol UDB-A 165 (roofing underlay)
A-classified (ZVDH), driving rain proof, highly vapour permeable roofing underlay for ventilated and non-ventilated pitched roofs. Suitable as temporary roofing up to 6 weeks (roof pitch > 16°). Available with or without self-adhesive strips.
Product description
TU-Berlin certified roofing underlay for pitched roofs
Alfa Rufol UDB-A 165 is the A-classified (ZVDH), driving rain proof, highly diffusion open roofing underlay (sub-membrane, sheathing membrane) for ventilated and non-ventilated pitched roofs. It is applied between the thermal insulation and main battens.
Suitable for the direct installation on top of the thermal insulation. Alfa Rufol UDB-A 165 prevents the penetration of humidity (e.g. due to driving snow) and penetration of dirt into the thermal insulation.
The 3-layer structure protects the functional membrane from damages and reduces the slipping risk for the processor.
Easy handling: Auxiliary lines allow exact overlaps.
Also available with two additional self-adhesive strips for easier application.
Advantages
- Meets the requirements of ZVDH and EnEV!
- Highly vapour permeable
- Step-proof
- Driving rain proof
- UDB-A / USB-A according to ZVDH
- Weight 170 g/m²
- Temperature resistance -40 up to +100°C
- Tear resistance (nail) >200 N/50mm
- Fire behaviour class E (EN 13501-1)
- Sd-value 0,02m
- Watertightness W1 (EN 13895-1)
- Tested by TU Berlin
Proven Quality

