The design brief had several limitations that factored into the final solution provided for the client. Access was limited to the general access lift. All pieces had to be constructed offsite, delivered, and installed just before the building opening.
The design inspiration came from the architect, Candalepas and Associates, who wanted to create a bespoke curved and intricate privacy screen between the two rooftop penthouse apartments which could be integrated with bench seating and be adaptable to allow for concealment of access for the rooftop spa equipment. The privacy screen had to follow the similar design profiles as per the rest of the building and polished, white glass fiber-reinforced concrete (GFRC) was the only product that could provide the result within the onsite constraints.
The privacy screen had to be robust and, as Stasia described it, "bulletproof" in terms of minimum maintenance and be able to withstand the exposure of a rooftop. It had to be structurally secure, yet be able to create intricate shapes and details. It had to make a statement.
The challenge was thrown to Concrete by Design as a consultant, system designer, and then fabricator/ installer. The project, overlooking the Sydney, Australia, skyline and harbor, demanded absolute accuracy in detail and finish. The first step was to map the entire project by 3D laser scan. This was then remitted to the screen and a full mold design was fabricated.
CbyD approached the design challenge by casting all pieces in a dedicated factory unit. As the wall was skinned both sides, two large skateboard-like ramp structures, about 50 feet long by 10 feet high, were built to allow the GFRC panels to be completed in one pour. This was a difficult approach, however, and much more accurate than building individual segments at ground level.
Scaffolding had to be installed to span and access the structure during the pour. Ridge caps and seating were then templated, laser scanned and cut, and then finished by meticulous handshaping. All pieces were trimmed, polished, and delivered, and transported in the lift to the rooftop penthouse.
The fixing system was custom-designed by CbyD with close to 200 individual stainless steel fixtures of numerous designs. The completed job exceeded the designer's and client's expectations. All of the curves in the walls, ridge capping, and seating run true without segmenting.
This project truly engaged leading edge technology, utilizing the latest scanning technologies, CAD works and robotic manufacture all combined with a great dose of old fashioned elbow grease. The results speak for themselves.