January 2017

N4 – Nexus, is a new £19 million office development for Surrey County Council, within the Manor Royal Business District of the Gatwick Diamond area in Crawley, with a colourful solar shading solution from Levolux.

The four-storey, 5,600 square metre office building has been designed by HGP architects to achieve a BREEAM ‘Very Good’ rating and an EPC rating of ‘A’. Two floors of the state-of-the-art building were pre-let by the South East Coast Ambulance Service (SECAmb), to create a new administration and call centre.

The building’s external envelope features floor to ceiling glazing on east, west and south-facing elevations. This helps to allow natural daylight to flood the building and by providing occupants with attractive outward views. To complement the glazing, Levolux was approached to design, supply and install an external solar shading solution.

Levolux devised a striking solution, combining fabricated and aerofoil-shaped louvres, fixed vertically and horizontally, respectively.

In total, Levolux manufactured 136 fabricated aluminium louvres, each measuring 750mm wide by 100mm thick, with a rectangular profile. The louvres are fixed vertically, extending up to 4 metres in height, between floorplates.

The louvres project 90 degrees from the building envelope and are distributed across east and west-facing elevations on each of the building’s four levels. A horizontal rainscreen bulkhead has been incorporated between each floor, fitted to the leading edge of the louvres.

The bulkheads, each measuring 500mm wide and formed from 3mm thick sheet aluminium, create a series of horizontal lines that soften the visual impact of the building.

To the south-facing elevations, Levolux utilised its Infiniti Fin system to create a series of horizontal, aerofoil-shaped fins, each measuring 200mm wide. The vertically stacked fins are set at a pitch of 250mm and are fixed at an angle of 28 degrees from horizontal, providing an effective sun cut-off angle.

Across south-facing office areas, aerofoil-shaped fins have been incorporated into a series of vertical stacks that continue across two elevations. The horizontal fins are grouped together at high level on each floor, starting with 7 fins above ground level, while each of the upper three floors is fitted with 4 fins.

All horizontal fins are secured to continuous, vertical aluminium carrier arms, which are set at approximately 3 metre centres. In addition to the concealed fixings, another benefit of the Infiniti Fin system, is that fins can be cantilevered beyond the last vertical support. This creates a clean, continuous aesthetic that other systems cannot match.

The building’s main entrance is set into the centre of the south-facing elevation, with a full height glazed façade that extends from ground to roof level. To prevent excessive solar heat gain from occurring in this area, the same 200mm wide aerofoil-shaped fins were used, but here they are fitted in a continuous vertical stack.

In total, 50 fins combine to form a vertical stack that measures 9 metres wide by 12.5 metres in height, extending from first floor to roof level. The fins are set at the same angle and pitch as the fins fitted elsewhere.

To create the optimum configuration for the external solar shading and its integration with the curtain walling, Levolux incorporated its patented Triniti bracket. By incorporating a comprehensive thermal break, the Triniti bracket effectively minimises heat loss and noise transmission.

While the aerofoil-shaped fins, carrier arms and bulkhead features have been given a highly durable powder coated finish in a subtle grey colour, the large fabricated louvres steal the show, finished in a bright green colour.

This is the first of six buildings to be earmarked for a former 10 acre Thales site to the south of Gatwick Airport. The completion of the N4 building, with its green vertical louvres, promises to provide an attractive and highly sustainable new home for local organisations.