How does one navigate the complexities that contours present when designing on steep terrain? Using The Island Masterplan as an example, Architect Claire Devanney describes the key principles used to overcome the challenges of creating a new community and destination on a steep site in Cyprus.

The Island Masterplan introduces a new private school with associated boarding houses, residential neighbourhoods, and a research and development hub to a 33-hectare site in Palodia Village in Limassol, Cyprus. The steeply sloping hillsides of the site offer incredible views towards the surrounding mountains and valleys and have informed the overarching masterplanning principles. The relationship between buildings, landscape and contour lines has evolved throughout the design process. One of the core design principles has been the creation of buildings that lightly touch the ground by stepping down the site on shifted planes, perpendicular to the contours.

THE SLOPING SITE

The main challenge of this rural site is immediately presented by the complex sloping terrain which varies in steepness. A digital ‘grasshopper’ script was used to determine the steepest areas of the site, and areas with a shallower gradient. With upwards of 100m vertical gain across the site, the contrast between red and green areas highlights the variation in gradient of the hillside terrain.

Carefully chosen section cuts (drawn perpendicular to the direction of the contour lines) indicate that the gradient of the slope is 29 degrees at the steepest location. Through this analysis, the team were able to determine the most viable places to build. The ambition for the proposals was to maintain the natural topography where possible, and to minimise the amount of cut and fill required; - an earthmoving technique used to provide level access on steep slopes.

Buildings within the masterplan are therefore primarily located in areas with a shallower gradient, whilst landscaped zones are created in areas with steeper gradients. The landscaping and steeply sloping existing terrain is used to define public and private zones and extends and flows between buildings to establish strong connections between sequential indoor and outdoor spaces.

A comparative study was undertaken for the potential urban grain by overlaying plans of existing successful examples of established European piazzas onto the site. This highlighted the contrasts in scale and informed initial urban design explorations.

DESIGNING PERPENDICULAR TO THE CONTOURS

Designing perpendicular to the contours maximises the amount of building façade that can be exposed on a steep site. As the downward slope on the site is north facing, orientating residential blocks perpendicular to the contours creates the optimum plan form for east-to-west facing apartments whilst increasing the opportunity for natural light and ventilation, and improves efficiency in terms of minimising ‘cut and fill’.

In all the locations with steep terrain, residential apartments and villas, the school, and boarding houses were designed to step down the hill. The buildings were orientated to follow individual axes running perpendicular to the contours on the steeper ground. These axes form a radial grid that spans around the northern sector of the site, towards the foot of the local escarpment. Buildings that follow the same axis are grouped together to form a neighbourhood, each with a unique character reflected in the façade strategy, materiality and landscaping. The juxtaposition of variable and contrasting materiality between neighbourhoods highlights their individual identity and enhances a sense of ‘place’ for residents. The ‘push and pull’ of building boundaries helps to define the edges of the interstitial landscaped spaces.

Within each residential neighbourhood, buildings sit parallel to each other with subtle shifts in positioning to minimise overlooking and enclose courtyards. The courtyards are further defined by the edges of terraced steps offering private and shaded spaces for residents. These adjacencies result in divergence and convergence of individual buildings within neighbourhoods, where the existing landscape is allowed cascade and flow between the buildings, juxtaposing the parallel terraced courtyards. Buildings are positioned at the optimum level on site to minimise impact on the existing landscape, whilst maintaining level access. In response to the sloping terrain, floor levels step down the hill on a sequence of shifted planes, allowing the roof of the offset level below to be used as a terrace. The stair cores are located at specific points on the floor plan serving each of the shifted floor planes. The section highlights the necessary contrast between the straight floor plane lines, and the organic naturalistic contours of the adjacent slope.

In the urban park (and some of the residential neighbourhoods), the basement levels sits below the urban piazza and the central landscaped spine that runs between the buildings. This important space is accessed at ground level from the lower part of the site at the foot of the hill and contains the parking facilities and services.

UPHILL AND DOWNHILL VILLAS

Villas are located at the highest levels of the site for privacy, and then cascade down the contours. Each dwelling sits on an individual plot and is positioned with the longer axis spanning the slope to maximise the potential for a shift in the stepped floor planes, and to optimise the opportunity for natural lighting, heating and cooling. This strategy, together with the offset between villas, preserves long unobstructed views for the villas behind.

Uphill' and 'downhill' villa typologies follow the principle of stepped levels to conform to the direction of the slope of the terrain. Inside, staircases are positioned deep into the floor plan on the entrance level to allow for the required uphill or downhill step. The extent of the offset of each level can be adapted further to respond to individual plot topography.

Living, dining and kitchen spaces are located where the building meets the terrain, allowing these spaces to open out towards the garden and pool areas. In downhill villas, the entrance is located on the upper floor alongside bedrooms. The layout has been carefully designed to provide the required level of separation between private and public spaces. In the smaller ‘uphill’ villas, the floorplan is reversed with the main entrance and bedrooms located on the ground floor with living spaces above.

The villas are made of locally available materials including stone, mud-brick and timber, and are in many cases partially built into the earth. This earth-sheltered design maximises use of the natural insulating properties of the soil, and further increases the protective thermal mass. Gardens are positioned to maximise the optimum aspect and sun path whilst terraced to respond to the sloping topography defined by different zones within the contoured sequence, helping to prevent soil erosion by reducing rainwater runoff. The material palette, landscaping and partial embedding of villas into the ground, allows for the buildings to blend harmoniously with their surroundings.

CONCLUSION

Although a site with steep terrain presents challenges, The Island utilises the constraint of the slope to create partially embedded buildings that integrate with their surroundings.

Designing buildings that sit perpendicular to the contours, with shifted floor planes that step down the slope is a common theme for many of the building typologies within the masterplan. This design principle reduces the requirement for cut and fill whilst offering a greater connection between outdoor and indoor spaces.

Throughout the masterplan, movement up or down the hill is supported by shifted floor plans within buildings. The careful positioning and shifting of building footprints maximises long unobstructed views of the hillside site, whilst enclosing landscaped zones that respond to their adjacent buildings.

A key design principle is utilising orientation along contrasting axes to define each neighbourhood. At the moments of divergence and convergence between separate neighbourhoods, a juxtaposition is created where the natural landscape spills through, in contrast to terraced neighbourhood courtyards. In addition to orientation, contrasting façade materiality strategies are used to further define individual neighbourhoods, with varied material colour palettes that reference the earthy tones of the site.

The uphill and downhill villas names directly reference the strategy used in response to their contrasting plot slope directions. As a result, The Island masterplan design process has unveiled a series of masterplanning principles that could be adopted and applied to the future development of sites located on steep terrain.

This article was written as part of issue Seventeen of Design Research Unit’s publication IA: Intelligent Architecture, dedicated to the theme: ‘Contrast and Juxtaposition’. To read the issue in full, click here.