Description

DriStud RU22 and DriStud RU24 are non-fire retardant, synthetic tri-laminate water resistant, absorbent and vapour permeable underlays. DriStud RU22 is grey-faced and DriStud RU24 is black-faced.

DriStud FRU36 and DriStud FRU38 are fire-retardent synthetic tri-laminate water resistant, absorbent and vapour permeable underlays. DriStud FRU36 and DriStud FRU38 are both white-faced.

All products are branded with DriStud branding and the specific product name.

Scope

1. DriStud RU22, DriStud RU24, DriStud FRU36, & DriStud FRU38 Roof Underlays are certified for use as a roof underlay:

• a) on buildings situated in wind zones up to and including Extra High (as set out in NZS3604) with a minimum roof pitch of 3°,
• b) under masonry tiles, terracotta tiles, metal tiles, profiled metal claddings, slate and composite panels,
• c) installed horizontally or vertically (subject to Condition 3 below)
• d) installed on timber or steel roof framing

2. DriStud FRU36, & DriStud FRU38 Roof Underlays are certified for use as a roof underlay and air barrier in locations exposed to view in an occupied space.

3. DriStud RU22, DriStud RU24, DriStud FRU36, & DriStud FRU38 Roof Underlays:

• a) shall be installed in accordance with the DriStud RU24 & RU22 Installation Guide Rev 4.0 (August 2023), the DriStud FRU36 Installation Guide Rev 4.0, (March 2019) and the DriStud FRU38 Installation Guide Rev 3.0 (March 2019) respectively (available at www.drispace.co.nz)
• b) shall be supported by corrosion resistant mesh or alternative e.g. plastic strapping where:
  
  • i. the span exceeds 1200mm or
  • ii. the underlay is installed vertically where the roof pitch is less than or equal to 10°, or
• c) may be installed horizontally (with upper layers overlapping the lower layers) without support, for roof pitches 3° or greater, provided the underlay is installed flat and taut,
• d) separated from fireplaces, heating appliances, flues and chimneys in accordance with the requirements of NZBC Acceptable Solutions C/AS1 and C/AS2, Paragraph 7.5.9 for the protection of combustible materials, and
• e) shall be protected from direct sunlight within 7 days of installation (21 days for FRU38).