Technical Statement
Product Description
Scope of use
Roof Application
- Suitable with masonry tile, metal tile and profiled metal roof cladding.
- Suitable for timber or steel framed buildings.
- Can be used on roofs up to and including NZS 3604 ‘Extra High’ wind zones.
- Self-supporting - Refer to installation guide regarding underlay support requirements.
- Not suitable for roof pitch less than 3 degrees.
- Will provide temporary weather protection during construction (maximum 7 days), same day coverage recommended.
Wall Application
- Can be used with timber and steel framing, either direct or in conjunction with an 18mm minimum drained cavity.
- Suitable with absorbent (e.g. timber, brick or fibre cement) or non-absorbent wall claddings (e.g. metal or plastic).
- Suitable with masonry veneer in accordance with NZBC Acceptable Solution E2/AS1 or NASH Building Envelope Solutions.
- Is suitable for use in Wind Zones of NZS 3604 up to and including ‘Very High’ when used as a standalone flexible underlay, and ‘Extra High’ when used as a flexible underlay over a rigid wall underlay.
- Is suitable as an air barrier in unlined wall spaces.
- Will provide some temporary weather protection during construction (maximum 60 days for wall application).
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), B2.3.1(c)
Clause B2 DURABILITY: Performance B2.3.1 (a), not less than 50 years, B2.3.1 (b), 15 years and B2.3.2. Covertek 405 Roof and Wall Underlay meets these requirements.
- Clause C3 Fire affecting areas beyond the fire source: Performance C3.4(c)
Clause C3 FIRE AFFECTING AREAS BEYOND THE FIRE SOURCE: Performance C3.4 (c). Covertek 405 Roof and Wall Underlay meets this requirement.
- Clause E2 External moisture: Performance E2.3.2
Clause E2 EXTERNAL MOISTURE: Performance E2.3.2. When used as part of the roof or wall cladding system, Covertek 405 Roof and Wall Underlay will contribute to meeting this requirement.
- Clause F2 Hazardous building materials: Performance F2.3.1
Clause F2 HAZARDOUS BUILDING MATERIALS: Performance F2.3.1. Covertek 405 Roof and Wall 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:
Roof Application
- Can be used as an underlay within the scope limitations of NZBC Acceptable Solution E2/AS1, Paragraph 1.1, with regards to building height and floor plan area.
- Or within the scope of NASH Building Envelope Solutions, Paragraph 1.1 for steel framed buildings.
Wall Application
- Can be used as a wall underlay within the scope limitations of NZBC Acceptable Solution E2/AS1, Paragraph 1.1, with regards to building height and floor plan area.
- Or within the scope limitations of NASH Building Envelope Solutions, Paragraph 1.1 for steel framed buildings.
Refer BRANZ Appraisal No 743 (2019) and CodeMark Certificate CMNZ 30030 RevH
Supporting evidence
The product has and can make available the following additional evidence to support the above statements:
Product Criteria
Installation requirements
Covertek 405 Install Guide
Maintenance requirements
No regular maintenance required.
Quality Assurance
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ISO 9001 (Quality Management) |
Relationships
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Member of New Zealand Green Building Council |
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New Zealand Made |
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Date last validated:
09 October 2023 |
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Date last updated:
09 October 2023 |