CSIRO has validated the weathertightness of the CSR Hebel residential external wall system as being compliant with the changes to the National Construction Code (NCC) that come into effect on May 1, 2015.

Ahead of the NCC changes taking effect next month, CSR Hebel initiated the process to test its wall system at the CSIRO using the proposed NCC Verification Methods. The completed weathertightness verification of the Hebel external wall system to the new NCC method provides the assurance of compliance to architects, designers, builders and tradespeople.

During the stringent testing at the CSIRO, a two-storey Hebel PowerPanel XL external wall system prototype was tested under static and cyclic water pressures in accordance with the test methods of AS/NZS4284:2008 – Testing of Building Facades. To ensure a complete verification of the Hebel product, the system included vertical and horizontal control joints, wall junctions at external and internal corners, a window, door, electrical box, balcony drainage and parapet flashing, the base of the wall at the slab junction and top of the wall to the eaves or parapet junction.

Architects and specifiers can be fully confident in documenting a building facade with this Hebel wall system validated by testing under the NCC Verification Method.

Hebel wall systems are proven weathertight products with over 20 years of success in the Australian market. Rigorous testing, continuing system innovation, stringent quality standards and a high level of technical support for the construction industry have all contributed to this longstanding record.

Lack of weathertightness can result in water penetration leading to unhealthy or dangerous conditions, loss of amenity, undue dampness and deterioration of building elements. While such problems are not so prevalent in Australia, New Zealanders have been living with leaking residential buildings for decades following a spate of poor construction standards relating to external wall cladding in the 1990s and early 2000s.

Repair and replacement costs in relation to the New Zealand crisis are estimated at $11 billion nationally over a 20-year period. Victoria has also experienced a few problems with non-compliant external wall cladding and a number of warnings have been issued.

Observing the incidents in New Zealand and Victoria, the Australian Building Codes Board has taken the initiative to protect occupants from problems related to weathertightness. These steps embrace recently introduced cladding systems (Alternative Building Solutions under the provisions of the NCC) and traditional ‘deemed-to-satisfy’ building systems including masonry veneer and full masonry external walls.

The NCC Verification Method provides designers with a risk matrix enabling them to assess a building facade wall system against risk factor, category and risk severity with corresponding scores. It also offers builders and tradespeople with greater assurance when providing a guarantee and warranty to the homeowner. The occupants also have the assurance of a rigorously tested system contributing to the weathertightness of their building envelope.