Technical Statement
Product Description
HYDRA Roof Underlay is a breathable, fire retardant, self-supporting, tri-laminate, flexible underlay.
Scope of use
SCOPE
HYDRA Roof Underlay has been appraised for use as a roof underlay for use 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; or,
- with metal tile and profiled metal roof cladding; and
- situated in NZ3604 Wind Zones up to and including Extra High
HYDRA Roof Underlay has also been approved for use on buildings subject to specific weathertightness design. Building designers are responsible for the building design and for the incorporation of HYDRA Roof Underlay into their design in accordance with the declared properties and the instructions of Marshall Innovations Ltd.
Building Regulations (NZBC)
3.1 In the opinion of BRANZ, HYDRA Roof Underlay, if designed. installed, used and maintained in accordance with the statements and conditions of this appraisal, will meet, or contribute to meeting the following provisions of the NZBC:
Clause B2 DURABILITY: Performance B2.3.1 (a), not less than 50 years, (b) 15 years and B2.3.2 HYDRA Roof Underlay will contribute to meeting this requirement.
Clause E2 EXTERNAL MOISTURE: Performance E2.3.2. When used as part of the roof cladding system, HYDRA Roof Underlay will contribute to meeting this requirement.
Clause F2 HAZARDOUS BUILDING MATERIALS: Performance F2.3.1. HYDRA Roof Underlay meets this requirement and will not present a health hazard to people.
New Zealand Building Code (NZBC)
The product will, if employed in accordance with the supplier's installation and maintenance requirements, assist with meeting the following provisions of the building code:
- Clause B2 Durability: Performance B2.3.1(a), B2.3.1(b)
Performance B2.3.1 (a), not less than 50 years, B2.3.1 (b) 15 years and B2.3.2 HYDRA Roof Underlay will contribute to meeting this requirement
- Clause E2 External moisture: Performance E2.3.2
Performance E2.3.2 When used as part of the roof cladding system, HYDRA Roof Underlay will contribute to meeting this requirement
- Clause F2 Hazardous building materials: Performance F2.3.1
Performance F2.3.1 HYDRA Roof Underlay meets this requirement and will not present a health hazard to people.
Notes
Clause B2 DURABILITY: Performance B2.3.1 (a), not less than 50 years, B2.3.1 (b) 15 years and B2.3.2 HYDRA Roof Underlay will contribute to meeting the requirement this requirement.
Clause E2 EXTERNAL MOISTURE; Performance E2.3.2. When used as part of the roof cladding system, HYDRA Roof Underlay will contribute to meeting this requirement.
Clause F2 HAZARDOUS BUILDING MATERIALS: Performance F2.3.1. HYDRA Roof Underlay meets this requirement and will not present a health hazard to people.
Evidence
The product meets the requirements set out in the following documents, or relevant parts of cited standards within the documents:
HYDRA Roof Underlay has been (BRANZ) appraised for use as a roof underlay in buildings as per scope of limitations of NZBC Acceptable Solutions E2/AS1.
Supporting evidence
The product has and can make available the following additional evidence to support the above statements:
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BRANZ Appraisal
1071 |
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Product Criteria
Design requirements
Please refer to HYDRA Roof Underlay Specification for technical product information, advantages and limitations.
Installation requirements
Please refer to HYDRA Roof Underlay Specification and BRANZ Appraisal # 1071 (2019) for full details of the installation process.
Maintenance requirements
HYDRA Roof Underlay must only be used under roof claddings which meet the requirements of the NZBC, such as those covered by NZBC Acceptable Solutions E2/AS1 or roof claddings covered by a valid BRANZ appraisal.
HYDRA Roof Underlay, when installed with the Technical Literature and this appraisal, will assist in the total cladding systems' compliance with NZBC Clause E2.
Warrantees
HYDRA Product Warranty - 15 years from date of purchase. Please view Warranty document via MWNZ website for full terms and conditions.
