Technical Statement
Product Description
Covertek 407 is our strongest synthetic underlay, designed as a means of managing condensation, water vapour transfer and water ingress in the most trying conditions including applications where the roof pitch is 3° and above.
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 some temporary weather protection during construction (maximum 30 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 (i.e. Gable ends).
- Will provide some temporary weather protection during construction (maximum 120 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)
Clause B2 DURABILITY: Performance B2.3.1 (a) not less than 50 years, B2.3.1 (b) 15 years
and B2.3.2. Thermakraft Covertek 407 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). Thermakraft
Covertek 407 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, Thermakraft Covertek 407 Roof and Wall Underlay contributes to meeting this
requirement.
- Clause F2 Hazardous building materials: Performance F2.3.1
Clause F2 HAZARDOUS BUILDING MATERIALS: Performance F2.3.1. Thermakraft Covertek 407 Roof
and Wall Underlay meets this requirement.
Notes
Meets the Performance Requirements of NZBC Clauses
B2, Durability (B2.3.1 (a) 50 years, B2.3.1 (b) 15 years
and B2.3.2), C3 Fire Affecting Areas Beyond the Fire
Source C3.4 (c) E2 External Moisture, and F2 Hazardous
Building Materials F2.3.1, providing:
- It is not damaged.
- Is installed in accordance with instructions.
- Is not left exposed for more than 30 days (roof) same day coverage recommended.
- Is not left exposed for more than 120 days (wall)
- Is installed by or under guidance of Licensed Building Practitioners.
- Is compatible with cladding system used.*
* Note: specifiers and product user must confirm roof and wall cladding system compatibility with the underlay before installation.
Evidence
The product meets the requirements set out in the following documents, or relevant parts of cited standards within the documents:
Compliance
Roof Application - Can be used as a roof underlay within the scope of limitations of NZBC Acceptable Solution E2/AS1, Paragraph 1.1, with regards to building height and floor plan area.
Wall Application - Can be used as a wall underlay within the scope of limitations of NZBC Acceptable Solution E2/AS1, Paragraph 1.1, with regards to building height and floor plan area.
Refer BRANZ Appraisal No 651 and CodeMark Certificate CMNZ30028 for full details.
Flammability Index - Covertek 407 Underlay has an AS 1530 Part 2:1993
Flammability Index of not greater than 12 and therefore
meets the requirements of NZBC Acceptable Solution C/
AS2, Paragraph 4.17.8 a), for the requirements of
suspended flexible fabric used as an underlay to exterior
cladding that is not exposed to view in occupied spaces.
Due to the updated scope of use limiting Covertek 407
to lined applications only, the flammability requirement is
now not greater than 12. Covertek 407 meets a
flammability index of not greater than 5, it is not
suitable for unlined applications due to UV control
requirements.
Supporting evidence
The product has and can make available the following additional evidence to support the above statements:
Product Criteria
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 |
Building Product Information Requirements
Manufacturer
Legal Trading Name:
Kingspan Insulation New Zealand Ltd
Business Email:
technical@kingspaninsulation.co.nz
Contact Number/s:
0800 806595
Product Identifier
CTS1250025 CTS1250050 CV2550075 CV2740050
Warnings
This product has no warnings associated with it.
