week 9

• Cladding


  The external protective layer used to protect a building
• Facade


  The external decoration of a building, the front part that faces an open space or street
• Facade


  Used when talking about design, style or colour
• Cladding


  There can be many options, but there is only one facade
• Cladding and roofing


  • Provides protection from the elements
  • For industrial buildings usually comprises steel roofing and walling
  • For residential and office buildings can include sheet metal profiles, zinc, copper, stainless steel and aluminum
  • Fibre cement wall cladding products are also commonly used in commercial construction
• Purlins


  Roof members used to support roof sheeting, run perpendicular to and supported on rafters
• Girts


  Wall members used to support wall sheeting, run perpendicular to and supported on columns and mullions
• Steel roof and wall cladding systems


  • Offered by suppliers with a wide range of profiles
  • Generally comprise flashings, gutters, downpipes and other accessories
  • All roofing profiles can also be used for walls, but specifically developed wall profiles are only able to be used for wall cladding
  • Steel thickness is specified by Base Metal Thickness (BMT) not Total Coated Thickness (TCT)

  
• NCC 2022 F3D2 Roof coverings requires metal sheet roofing to comply with AS 1562.1:2018 Design and installation of metal roof and wall cladding
• NCC 2022 F3D5 Wall cladding requires AS 1562.1:2018 Design and installation of metal roof and wall cladding to be complied with
• Wall cladding design


  • Straightforward once aesthetic decision is made
  • Main considerations are support spacings, fixing details and flashing details
• Roof cladding design


  • Considerations include shape, supporting structure and spacing, wind forces, pitch, thermal expansion, transportation, rainwater runoff, and fall protection
• Wind forces on roofs

  • Inward forces tending to collapse the roof cladding inwards
  • Outward forces tending to lift the roof cladding from its framing, caused by uplift from negative wind pressures and positive wind pressure inside the building
• Low roof pitches


  • Danger of ponding which can reduce service life
  • At slopes around 2° or less, all roof supports must be in the same plane
  • Minimum recommended slope is 1 in 30 (2°)
• Maximum length of roofs


  • Valleys (or pans) have to carry water to the gutters
  • Factors affecting waterproof and drainage capacity include valley width and depth, roof pitch, rainfall intensity, roof length, and penetrations
• Architectural metal cladding materials

  • Pre-painted aluminium
  • Copper
  • Brass
  • Zinc
  • Stainless steel
  • Weathering Steel/Corten

  
• Architectural metal cladding systems

  • Standing Seam and Snaplock
  • Interlocking
  • Flatlock
• Fibre cement wall cladding products

  • Linea Weatherboard
  • Matrix Cladding
  • Primline Weatherboard
  • Exo Tec
• Aluminium composite panels (ACP)

  • Attractive external facade solution due to thermal resistance, acoustic measurements and mechanical properties
  • Came under scrutiny due to fire behaviour, particularly in high-rise residential developments
• Effective 1 October 2018, the Queensland Government implemented laws regarding the use of combustible cladding on buildings to address safety concerns
• As of 1 September 2021, commercial buildings in Queensland must maintain a register of combustible claddings prepared by an appropriately qualified person
• Today's modern aluminium panels possess key qualities that separate them from the aluminium composite panels that raised safety concerns
• Effective as of 1 October 2018

  Queensland Government implemented laws within the Building Regulation 2006 regarding the use of combustible cladding on buildings to address safety concerns
• This law has been in a transitional arrangement since 1 September 2021 and may change at any time
• As the law stands today, commercial buildings must maintain a register of combustible claddings prepared by an appropriately qualified person
• NCC compliant aluminium panels

  • Rated as non-combustible and tested to Australian Standard AS 1530.1
  • Possess key qualities that separate them from the aluminium composite panels embroiled in the current crisis
• NCC compliant aluminium panels

  • MondoClad® solid aluminium panels
  • Alfrex Solid
  • Vitradual
  • ALPOLIC NC/A1
• Sarking


  A membrane of reflective foil draped over the supports before laying the cladding, providing heat control and a vapour barrier to minimise condensation
• Bulk insulation


  Blankets or batts used for additional heat insulation
• Condensation


  Water vapour in the air can condense on the inside of the cladding, leading to deterioration of building components and reduced insulation efficiency
• Provision of sarking will provide a vapour barrier to minimise condensation
• Design and buildability considerations for eaves gutters

  • Roof slope
  • Selected roofing profile
  • Penetrations
  • Catchment area of roof
  • Location, cross sectional area and gradient
  • Disposal of water from down pipes
  • Overflow precautions
  • Thermal variation (expansion joints)
• Design and buildability considerations for box gutters

  • Minimum width of 300mm for commercial, 200mm for domestic
  • Depth of sump heights not less than 150mm
  • 25mm free board
  • Thermal variation (expansion joints)
• Perimeter guard rails for fall protection

  • Incorporate a top rail 900 mm to 1100 mm above the working surface, a mid-rail and a toe-board
  • The guardrail system, method of attachment and the supporting structure should be capable of withstanding the loads that will be applied
• Safety mesh for fall protection

  • Designed to prevent internal falls through a roof
  • Should be used in conjunction with other fall prevention devices
  • Should comply with AS/NZS 4389: Roof safety mesh
• Safety mesh should be formed from 2 mm diameter wire, welded into a mesh with the longitudinal wires not more than 150 mm apart and the cross wires not more than 300 mm apart
• Safety mesh should be installed by competent people in accordance with the manufacturer's instructions
• Fall arrest systems


  • Intended to safely stop a worker falling an uncontrolled distance and reduce the impact of the fall
  • Should only be used if it is not reasonably practicable to use a fall prevention device or work positioning system
  • Equipment should be designed, manufactured, selected and used in compliance with AS/NZS 1891(set)4 : Industrial fall-arrest systems and devices