Watertight Roof Underlay
- Appraisal number 938
- 31 January 2019
- Valid from
- Information provider
- BRANZ Limited
- Information type
- BRANZ Appraisal
Watertight Roof Underlay is a synthetic building underlay for use under roof claddings.
The product consists of a micro-porous water-resistant polypropylene film laminated between two layers of spun-bonded polypropylene and is coloured grey.
Watertight Roof Underlay has been appraised for use as a roof underlay on buildings within the following scope:
- the scope limitations of NZBC Acceptable Solution E2/AS1, Paragraph 1.1 with regards to building height and floor plan area; and,
- with masonry tile roof cladding; and,
- with metal tile roof cladding; and,
- with profiled metal roof cladding; and,
- situated in NZS 3604 Building Wind Zones up to, and including Extra High.