Surface Design Awards – Complete

• EXTERIOR SURFACE OF THE YEAR - NEW
  This is a new category that recognises wall and surface design products including decorative, creative and inventive surfaces for the exterior of building including both commercial and residential properties.
• PUBLIC BUILDING - EXTERIOR
  Public Buildings used by the public for any purpose, such as assembly, education, entertainment, government, healthcare, transport or worship. This will also include civic centres, community centres, libraries, visitor centres, culture, health + wellbeing, faith, education, sports venues and stadia, transport, central + local government, entertainment and event venues.

A 600m² rooftop walkway and 360° viewing platform on the 26m high former air traffic control tower, constructed with Kebony Clear wood decking, as part of the wider redevelopment of Berlin’s historic Tempelhof Airport.

The new exterior installation at the THF Tower marks a significant step in the regeneration of the former aviation centre which closed its hanger doors in 2008. The wood-panelled rooftop terrace creates a new exhibition and event space, offering visitors not only stunning views across the skyline of the German capital, but an expansive viewing platform to experience the regular programme of cultural events hosted at the airport, including trade fairs, concerts, such as annual Tempelhof Sounds festival, and sports events, including the 2023 Berlin Formula E-Prix.
The roof terrace is characterized by a distinctive three-dimensional slope, and offers an attractive viewing platform which descends over several steps to the edge of the tower. In the centre of the terrace, the main level narrows and additional intermediate height steps have been added to the sides, accommodating the subtle change of shape. This challenging design required a robust and durable substructure. The substructure skeleton, which extends over the entire roof of the airport tower, forms both the roof terrace and the transitions between the individual steps, with the height of the substructure varying from five centimetres at the lowest point, to 70 centimetres at the highest point. To compensate for these height differences, a combination of concrete and gravel was used. The resulting terrace sweeps in a gradual ascending arc from one end of the tower to the other, with the elegant lines of the Kebony decking culminating in a raised central platform that rests in front of the glazed tower dome at its edge. This platform is south-west facing, allowing for spectacular sunset views, with the lengthening shadows accenting the surface of both the Kebony wood and the tower’s control centre.

In order to meet the special construction requirements of the tower context, including the wind load, fire protection, and pressure load, an innovative concept for the substructure of the terrace was developed by Karle & Rubner, in close cooperation with their various construction partners and architects :mlzd. The substructure consists of adjustable plastic supports placed on an insulation and waterproofing layer. These supports carry a bearing structure made of aluminium profiles, on which the Kebony Clear wood decking was finally laid, spanning the length of the terrace and intersecting at angles with the graduated step structure on its edge, and with the base of the control tower itself. Concrete slabs provide the necessary weight at potential weak points in the structure. This system offers a high degree of flexibility in terms of height adjustments and levelling, which is important to compensate for unevenness in the underlying structure, and allows for the visually striking final result. The newly developed substructure has the potential to be incorporated into future projects of this kind: by making it possible to respond to different structural conditions, the sophisticated design offers an excellent solution for terraces in challenging environments.

Requiring a decking surface capable of managing the exposed location of the project, Kebony Clear decking was selected to give the space a durable and visually sophisticated finish. Developed in Norway, Kebony wood provides a sustainable alternative to tropical hardwoods, helping to ease the global dependence on traditional construction materials, thereby reducing the continued environmental damage caused by deforestation.

Through the production of enhanced dually modifiedTM timber, sourced from sustainable softwoods such as pine, Kebony offers architects a wood product with the same build characteristics of protected wood species such Ipe and Cumaru, without the same cost to the carbon footprint. Their patented dual modificationTM process permanently transforms the wood cell walls to become 50% thicker, forming locked-in furan polymers in a two-stage process. The wood is first infused with furfuryl alcohol produced from a bio-based liquid to make it dimensionally stable, before being cured in a heating process. The dimensional stability, durability, and hardness of the wood are all increased, guaranteeing both a long life and a high level of safety.

Kebony’s patented modification process enhances the dimensional stability of the wood cell walls, and, over time, its surface develops a silver-grey patina that adds depth and character. This unique combination of features renders Kebony an ideal solution for projects like the THF Tower terrace, that are constantly exposed to the elements, but still require the highest standards in design aesthetics, durability, and sustainability.

The successful implementation of the THF Tower project is a demonstration of the innovative ways in which historical, high-carbon emitting industrial sites, such as decommissioned airports, can be repurposed into new long-term social and sustainable contexts. Renovating the existing structures, as opposed to replacing them wholesale through demolition and reconstruction, prevents the release of millions of tonnes of embodied carbon into the atmosphere.

Kebony wood products consist of renewable wood and predominantly bio-based chemicals. While tropical hardwoods can take 80-200 years to grow, fast-growing softwoods used for Kebony products, such as Pinus Radiata and Pinus Silvestrus, grow in as little as 25-30 years. During the growth of the trees and crops used as raw materials for Kebony, carbon is captured from the atmosphere, contributing to a global reduction in CO₂ through carbon sequestration.

For the reporting year January 1st to December 31st 2022, Kebony products produced are calculated to have assimilated 25,773 tons of CO2 equivalents. More specifically, Kebony calculates an estimated emissions saving of 143,000 metric tons of CO2 had Kebony products been substituted in place of the total US and EU sales output of Ipe hardwood materials across 2022.

Kebony also sources timber from forestry based on sustainable practices, certified by the Forest Stewardship Council, FSC, thereby satisfying demand for hard, durable timber whilst protecting vulnerable pristine forests. As a company, Kebony developed a Greenhouse Gas (GHG) inventory as a first step in their ambition to be Net Zero by 2035, and committed to the Science Based Targets initiative in 2022.

The combination of the building’s historical character and modern construction requirements presented architects :mlzd and designers Karle & Rubner with a unique challenge. When choosing the materials for the roof terrace, accessed via a suspended steel staircase that guides visitors up from the central terminal, both the technical and aesthetic characteristics of the building product were paramount to create a quality, long-lasting facility to support regular use.

Since wood was not an option as a material for the substructure due to fire regulations, aluminium profiles were used. Structurally, the building was never properly completed in its original construction. In addition, there is no building permit for the building, and thus no proof of the safety of the supporting structure and fire protection. These challenges were solved through a careful analysis of the existing building fabric and close cooperation with the responsible parties. The planned use of the terrace as a public space necessitated the highest demands on all aspects of the structure, including statics, load tolerances, and wind suction resistance. Numerous possible solutions had to be discarded before the final design could be implemented, with the suitability and adaptability of Kebony wood in demanding environments a key factor in delivering the finished project.