By Lyn Drummond
28 November 2011 – Almost three years since being destroyed in the Victorian bush fires, the new timber Narbethong Community Hall was opened on Saturday, 26 November, by the Governor of Victoria, Alex Chernov.
Ninotschka Titchkosky, prinicipal of architects BVN, said one of the greatest challenges was designing a timber hall in an area that has a very high rating of bushfire protection.
“In order to meet the bush fire requirements the outside of the building is made up of floor to ceiling double glazing that is wrapped in a bronze mesh fire resistant screen,” Ms Titchkosky said.
There were several drivers for the project, she told The Fifth Estate.
“We wanted to create a new hall that reflected the heritage of Narbethong as a timber town. Unlike the previous hall we wanted a space that enabled you to feel connected to the natural surrounds and was less defined between inside and out. Low operation costs were important and we were required to meet strict bushfire attack levels.
“ It was unlikely anyone would be available to defend the building in the case of fire (as they would be focussing on their homes) therefore the building needed to be able to be locked down when not in use.
“These were the key things that led us to the design outcome of essentially a glazed box of floor to ceiling glass (with some solid infill where service areas occur) covered with a fire rated mesh (that also acts as fly screen, security mesh and sun control) with an all timber interior.
“The Crimsafe mesh and aluminium plates cover all external vertical surfaces of the building and essentially make it fire proof.
“The mesh screen had to be carefully designed to ensure that no gap was greater than three millimetres to stop ember attack.
“Behind the screen all solid walls are fibre cement sheet and glazed walls are double glazed high performance glass supported by blackbutt timber mullions.”
The blackbutt is one of the bush fire retardant timber species which is allowable in Bushfire Attack Level 29 categories.
The timber mullions also offered the additional performance measure that they stop cold bridging from outside to inside.The timber is only oiled (no special treatment is required) Blackbutt mullions are 45 millimetres x 150 mm.
Ms Titchkosky said internal selections were slightly limited but “we were able to achieve Messmate timber floors, ceilings and timber fins for the curved walls.
“When the hall is in use the large tilt up screens at the front entry to the south and to the lawn on the north can be opened to provide uninhibited views and access to external spaces. When the hall is not in use the automated tilt up screens are closed, sealing the full perimeter of the building for fire protection.”
There is no additional fire protection except for the fire pump for fire trucks which links to the underground water tanks.
The building is a slab on ground to stop any fire sources from the ground or under the building and the roof is a standard colour bond roof.
“We were very careful to limit penetrations through the roof and most ducting comes out the walls hidden behind the mesh screen.
“Finally the intent being the hall needs to look after itself in the case of emergency and not rely on tricky operable systems.”
Internally the primary material is local timber. The timber floor, ceiling and curved screen are all expressions of Narbethong’s history and the 4.2 metre high verticals of the timber screen are reminiscent of the beautiful trees found in the region and the Black Spur Forest.
A working bee has planted nearly 3000 tree, shrubs and grasses – many of which were donated to complete the landscaping in time for the opening.
The new hall is the result of a pro-bono collaboration with other consultants including, BSGM, Rodney Vapp & Associates, Contour Planning, Rodney Aujard & Associates, Douglas Partners Pty Ltd, Fitzgerald Frisbee Landscape Architecture, who then worked in conjunction with Edwards Moore, Hedger Constructions, The Victorian Bushfire Recovery and Reconstruction Authority, DSE, Murrindindi Shire and the Narbethong Public Hall Committee to design and implement the rebuilding of the Hall, which was made possible with McDonald’s major sponsorship of $520,000