AU2015100652A4 - Bushfire rated metallic roof infill strip casing with optional insert - Google Patents

Abstract

Abstract The application refers to an element within profiled roofing and wall cladding systems as used in commercial and domestic construction. Our system is an eave sealant (referred to as "RIS) that encloses the profile gap between the purlin & roof . The Building Code Australia (BCA) requires that in bushfire designated areas all systems used for this function, must conform to AS3959 or be constructed from elements that are certified as non-combustible as per AS1530/1. The application therefore is for a RIS with an external facing that conforms to AS1530/1 that consists of either a face & base (Figi), a face, base & small back (Fig2) or a face and a full back (fig3) all of which match the profile of the roof being used, then a secondary material is inserted into the unit to create a dust and air seal (fig6). Fig 1 Fig 1-G Fig 2-E Fig 3-F Fig 3 Fig 4 Fig 5 Fig 6-H ig 6

Description

1 Title Bushfire rated metallic roof infill strip casing with optional insert Technical field Profiled roofing and wall cladding systems for use in commercial, agricultural and domestic construction Background [0001] The applicant contends that where a particular system has been certified to meet the requirements of AS3959 then any change to the system negates the certification. A change would include using a different profile or material. [0002] As the manufacturer of RIS the variations of systems is beyond our commercial ambit therefore to market RIS as a product for use in any profiled system they must conform to AS1530/1 to meet the Bushfire ratings as set out within the BCA Summary of invention Technical problem [0003] To meet the BCA Bushfire rating to prevent external attack of radiate heat and the ingress of sparks and embers whilst maintain the seal integrity against transmission of air, moisture, dust and vermin into the whole system [0004] Seal integrity is currently provided by standard polymeric RIS's constructed from materials such as closed cell thermoplastic foams, cellular rubbers, chemically impregnated open cell foams mineral fibre or glass fibre or resin impregnation of bound ceramic materials [0005] All such materials, including those that meet the requirements of AS1530/3 for internal fire rating, fail the requirements of AS1530/1 for external resistance to fire. Therefore are not certified for use in a designated Bushfire zone.

2 [0006] In addition to this failure many of these materials utilize retardant systems within their chemical structure that produce toxic fumes and release of non ROHS substances when activated by fire. [0007] Their fire degradation leads to gaps within the system that allows the ingress of radiate heat and sparks and ember ingress therefore propagating the fire. The construction is therefore exposed to the after fire front attack Solution [0008] The applicant proposes a RIS manufactured from a metallic composite that meets the non combustible requirements of AS1530/1 and has sufficient rigidity to maintain its dimensional integrity under attack by external fire. [0009] The proposed RIS encloses the internal RIS (without regard to its material construction) on its external face , turning perpendicular to cover the purlin/girt face to seal any dimensional variation in the purlin alignment or surface, it can the optionally turn again perpendicular to be upright at the rear of the internal RIS. [0010] A further option can be added whereby the proposed RIS can be constructed with overlapping tabs that pass over the profiled side of the standard RIS thus clipping the proposed RIS to its rear face. [0011] The proposed RIS can be manufactured in any profiled shape to suit the cladding profile. [0012] The proposed RIS can be manufactured in any dimension to suit any variation of thickness of the inner RIS. [0013] The proposed RIS encases the internal RIS but can be installed as a standalone product or as an external cladding to a standard RIS.

3 Advantages [0014] The proposed RIS enables a rigid standalone external facing of the profile gap to BCA Bushfire Protection standards. It provides external fire rated encasement of inner RIS therefore the integrity of dust moisture air and vermin resistance is not compromised and it will not aid propagation of fire. [0015] The RIS casing can be manufactured to suit any cladding profile, any cladding size as well as in any suitable metallic material that can match the metals of any roof to avoid oxidation and or electrolysis. Description [0016] The proposed RIS provides a certified external fire resistant encasement with base and optional internal encasement of the standard RIS to seal the gap of the profiled cladding in a roofing or cladding system [0017] When used in conjunction with a standard RIS it can solve all system sealant issues. [0018] When used in conjunction with chemical resistant polymers for the manufacture of the internal RIS it seals against fire externally and internally in addition to the escapement of gases and toxins within the building without degradation of all sealant issues.

Claims (6)

1. The proposed RIS is certified to AS1530/1 non combustibility

2. The proposed RIS externally encases the inner polymeric RIS

3. The internal RIS can be made to conform to AS1530/3

4. The inner RIS maintains the integrity moisture, air, dust & vermin seal

5. The proposed RIS provides an external facing that conforms to the Bushfire requirements of the BCA

6. The proposed RIS can be manufactured in a variety of metals to avoid oxidation and electrolysis with metal roof sheets