DriStud FRU 38 Fire Retardant Synthetic Self-Support Roof Underlay

Scope of use

Scope

DriStud FRU 38 is a synthetic roofing underlay that are intended for use on new and existing buildings in wind zones up to and including "Extra High", as desfined in NZS 3604:2011.

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 B1 Structure: Performance B1.3.1, B1.3.2, B1.3.3(a), B1.3.3(h)
• Clause B2 Durability: Performance B2.3.1(a), B2.3.2(b)
• Clause C3 Fire affecting areas beyond the fire source: Performance C3.4(c)
• Clause E2 External moisture: Performance E2.3.1, E2.3.7(a), E2.3.7(b), E2.3.7(c)
• Clause F2 Hazardous building materials: Performance F2.3.1

Supporting evidence

The product has and can make available the following additional evidence to support the above statements:

	CodeMark AQ-100915-CMNZ

Product Criteria

Design requirements

USE

DriStud FRU 38 is intended for use on buildings designed in accordance with NZS 3604:2011 paragraph 1.1 and in wind zones up to and including ‘Extra High’. DriStud FRU 38 is designed to be used as a replacement for standard kraft paper roof underlay.

It can be installed over both timber and steel framing to ensure a dry roof cavity. DriStud FRU 38 can be used under: Masonry tiles Metal tiles Profiled metal roof claddings However, DriStud FRU 38 must not span more than 1200mm between adjacent supports.

Installation requirements

Overlaps / support

DriStud roofing underlays must be installed with all writing and imagery facing out and with as minimal a number of overlaps as possible. Where overlaps are unavoidable a lap of 150 mm minimum must be used. DriStud FRU 38 must not span more than 1.2 m between adjacent supports. The installation of DriStud roofing underlays must be in accordance with paragraph 8.1.5, E2/AS1.

Installation

If the roofs pitch is 10° or less, DriStud roofing underlays must be run horizontally with the higher layers sitting on top of the lower layers. If installing on a roof with a pitch greater than 10° then DriStud roofing underlays may be installed either horizontally or vertically. When DriStud roofing underlays are being used in conjunction with masonry tiles, antiponding boards should be used at the lower edges of the tiles. 

Maintenance requirements

Maintenance

DriStud roofing underlays do not require any maintenance but when exposed through removal of roof cladding, the underlays must be inspected and any damaged areas repaired or replaced.

Warrantees

Warranty

TCL Hunt Ltd warrants that all DriStud roofing underlays will be free from manufacturing defects. Upon receiving of DriStud roofing underlays, it is recommended that a visual check is made. Where defects are observed, these will be replaced at the discretion of TCL Hunt, provided that they are returned to point of purchase.

If installed in accordance with TCL Hunt installation requirements, TCL Hunt warrants that DriStud roofing underlays will comply with all relevant provisions of the NZ Building Code. TCL Hunt is confident that all DriStud roofing underlays will have a serviceability life of 50 years provided that:  

• the balance of the external wall is installed in accordance with the NZ Building Code, and,
• all necessary maintenance is undertaken in respect of the external wall system.

Please refer to DriStud website www.dristud.co.nz for more information on warranty and disclaimer. 

Company Product Information

Quality Assurance

ISO 9001 (Quality Management)