Greene Fire completed a challenging installation of fire curtains at The Hub in Martin Place, NSW.
Comprising of seven floors of office space connected via an open circulation stair, The Hub has been designed to accommodate approximately 1535 people. The interconnection of the seven levels created a single fire compartment.
However, the base building stair pressurisation system was only able to deal with two interconnected floors in order to maintain the required airflow (1m/s) across each fire stair door. This meant separate fire compartments had to be created for every two interconnected floors. Additionally, there were a number of stairs and voids that connected through all levels; these were separated using a combination of horizontal and vertical fire curtains, glazing, wall wetting, and fire rated construction.
The fire compartment size exceeded the limits imposed by DtS provisions (>8,000m²). By combining active and passive fire rated construction, the fitout was separated into fire compartments in fire mode with the largest fire compartment approximately 4700m² to satisfy DtS requirements.
The contractor had a choice of fire curtains, fire rated glazing, and conventional fire rating to fire rate around the void.
Greene Fire solution
Greene Fire installed a horizontal fire curtain underneath the level 6 stair void – the largest simplex horizontal curtain supplied to date measuring approximately 9.5 metres wide x 9.5 metres long. However, the main challenge was not the installation but getting a product of this size into the building. Typically, products used in large installations are sent to the site in smaller parts and then assembled and welded on-site. This option was not available for Greene Fire as the fire curtain was manufactured in the UK and the fabric roller and side guides could not be cut down.
Greene Fire resolved the problem by setting up a boom lift, removing a window on the Pitt Street side of No. 1 Martin Place and using a 90-tonne crane to lift the large crate into the building. This process required a lot of planning, given the building’s location in the heart of Sydney.
Another challenge involved getting the fire rated glass to its installation location on Levels 3, 4 and 5 due to the size and weight of each piece of glass. The Contraflam 31mm thick glass consisted of five layers and the 1300mm wide x 2740mm high panes weighed between 200kg and 230kg each. The glass was delivered to the loading dock and manpower/mechanical aids used to get each pane to its location.
The 13m wide single roller fire curtains were installed on Levels 3, 4, 5 and 6. Greene Fire worked closely with the builder and design team from early design concept stage right through to handover to provide the optimal solution of openness, security, fire protection, functionality and architectural design.
Benefits of Greene Fire fire curtains
By installing fire curtains from Greene Fire throughout the fitout, wide open spaces could be created while still providing the occupants with a safe workplace. In fire mode, occupants would be able to evacuate through the retractable fire curtains and doors in the fire rated glass walls. The use of a horizontal fire curtain underneath Level 6 separates the two floors above from the fire compartments below. The use of wide single roller vertical fire curtains allowed the existing walls to be used as a structure for fixing the fire curtain to, while maximising the floor area and open space.