Oasia Hotel Downtown / WOHA / Singapore

Oasia Hotel Downtown 

• Architects:  WOHA Architects
• Location:  Singapore
• Client:  Far East SOHO Pte Ltd  
• Civil & Structural Engineer:  KTP Consultants Pte Ltd.  
• Project Dates:  Design Inception: 2011;  Construction Start:  2012;  Completed:  2016
• Project Cost:  $138 Million (estimate)
• Building Function:  Hospitality, Hotel + Hostels + Guest Houses
• Gross Floor Area:  19,416 sq.m
• Plot Area:  2,311.4 sq.m
• Building Height:  193.3 m / 634 ft / 27 stories
• No. of Offices:  100 Offices
• No. of Hotel rooms:  314 Hotel Guestrooms (224 Hotel Typical, 88 Hotel Club, 2 Suites)
• Mechanical & Electrical Engineer:  Rankine & Hill (Singapore) Pte Ltd  
• Quantity Surveyor:  Rider Levett Bucknall 
• Landscape Consultant:  Sitetectonix Pte Ltd  
• Irrigation Consultant:  Christensen Irrigation (Singapore) Pte Ltd  
• Lighting Consultant:  Lighting Planners Associates (S) Pte Ltd The Lightbox Pte Ltd  
• Main Contractor:  Woh Hup (Private) Ltd  

Oasia Hotel Downtown is a prototype of land use intensification in the tropics. Unlike the sleek and sealed skyscrapers that evolved  in the temperature West, this tropical "living tower" is designed to soften the hardness of the city and to reintroduce biodiversity into the urban jungle.

Responding to the client's requirements for district offices, hotel and club rooms, the tower comprises lushly landscaped sky terraces, inserted in naturally ventilated breezeway atria between room blocks. These provide guests and occupants generous amenity spaces throughout the high-rise with dynamic internal views that frame, soften and distance the surrounding dense urban fabric.

From Vertical City  ...

The modern tower has evolved as a suite of engineering solutions and financial efficiencies - maximized volume-to-surface area ratio, compact centralized core, open plan floor plates and high-performance, shiny skins. Inhabitants are kept comfortable by mechanical means. While boasting efficient structures and systems, buildings still account for nearly 40% of global energy consumption; of this, up to 60% is consumed by the common areas in buildings. In a "vertical city," people are stratified and confined leading increasingly, insular lives, with minimal contact with nature.

To Garden City ...

The modern tower, as a building block of cities, can be reinterpreted as infrastructure, with greenery and amenities that support and contribute to the overall urban environment. It can be systemically incorporated as part of the master plan and an overall urban design for reinvigorating cities. By incorporating greenery beyond the ground plane, buildings can become biophilic environments that visually and emotionally engage the inhabitants and public. Research into biophilia shows that there is an innate relationship between human and nature, and that humans have a fundamental need in order to maintain a sense of positive well-being, productivity, creativity, and delight. The availability and experience of green environments make cities more humane, healthy and livable.

Oasia Hotel Downtown:  An Oasis

Located in the heart of Singapore's Central Business District (CBD) and overlooking the historic Tanjong Pagar District, Oasia Hotel Downtown is distinctive in its expression, forming a spectacle of architectural design and engineering. 

Hemmed in by high-rise, 191-meter tower rises up from the tree-lined streets as a verdant tower of green, presenting an alternative imagery, against the concrete and glass cityscape. It offers a vision of a new typology for the tropical skyscraper - one that is suited to the local climate, with internal breezeway atria, multiple sheltered terraces, sky gardens and vertical greening. Opened in April 2016, the tower has quickly become a beacon of nature and an oasis in the city's dense surroundings.

Integrating Mixed Uses -

The brief called for three distinct components - strata-tilted offices, standard hotel guest rooms, and club guest rooms - within a single tower on a tight 47-by-47 meter site. Although housed within a single building, the office and hotel/club components needed to be separated from each other for security, as they cater to different user groups. The hotel and club operate separately under the Oasia brand, with a shared back-of-house.

Sky Terraces -

With the cores located in the corners, the sky terraces allow a unique 360 degree view through gardens to the city, which would not have been possible with a typical center-core tower. Despite the limited footprint, public areas the size of the ground plane are multiplied four times throughout the tower. The planting that surrounds and stretches all the way to the edge of each sky terrace reinforces the impression of the ground.

Breezeway Atria - 

The L-shaped blocks, set onto a square plan, result in 21 to 35 meter tall breezeway atria at each sky terrace. The sky terraces also serve as huge overhangs, directly shading the terrace below. Open-sided, the atria are cross-ventilated from all directions, aided by a natural funneling effect. Each atrium achieves an approximate 1:1 height to depth ratio, affording a bright and airy environment with daylight and cross breezes, coupled with evaporative cooling from water and shading from greenery. The atria also carve out spaces that offer dynamic internal garden views, while framing, softening, and screening the surrounding dense urban fabric.

Living Screens - 

The tower has neither a solid mass nor a full height curtain wall. The stacked blocks and terraces are enveloped by 25,000 square meters of expanded aluminium mesh screens. About 1,800 prefabricated fiberglass planters are located on every story, abutting the screen so that creeping vines are only required to climb three to five meters before overlapping with the next tier of planters. Over time, the vines will spread over every surface. Landscaping is used as the architectural environment filter and material palette, not as a cosmetic add-on. As an envelope, the greenery and the screen function as filters that provide shade, reduce heat, dampen noise, cut out glare and dust, and improve air quality. As a finish, the screen is a composition of five colors - red, dark red, pale pink, fuchsia and orange.

Man-Made Ecosystems -

Twenty-one species of creepers were selected and distributed across the facades, based on their sunlight requirements, rate of growth, density of coverage, texture, and color. Some species produce colorful flowers that attract birds and insects at different times of the year. With the facade coming close to existing roadside trees and landing at ground level, the building extends those existing roadside habitats vertically. Together with 33 different species of trees and shrubs planted on the sky terraces, there are a total of 54 species of plants within this living tower. The variety of plants also provide natural resilience against disease carrying and destructive insects.

A Prototype for Livability and Sustainability - 

With all green and blue surfaces amalgamated, the tower achieves an unprecedented overall GPR of 1,100%. Put another way, it provides 10 times as much greenery to the plot as was originally on the undeveloped site. It effectively compensates for the lack of green in 10 additional sites of equivalent area. Beyond this, the tower demonstrates generosity and good citizenship by giving back to the city. Within the building, people are surrounded by nature. Around the building, the vertical green screens and landscaped sky terraces provide a welcome respite to the built urban environment. The tower is a biophilic three-dimensional environment that heightens the human experience of nature - within the building interior or as the next door neighbor, up close at the urban street level, from afar at city level - bringing a sense of beauty, poetry, surprise, discovery, and delight to everyday life.

Conclusion -

It is important to see architecture as more than a collection of seductive forms and facade and to bring the attention  back to architecture's capacity to create human-centric environments. Oasia Hotel Downtown is a striking spectacle, and environmentally friendly, culturally appropriate, and climatically sustainable. It is a prototype that re-imagines a tall building as a responsible, livable and sustainable high-rise environment that contributes to the city on different levels.