The Altitude Colombo, Sri Lanka

By June 27 , 2016
Ar. Reza Kabul
Ar. Abin Chaudhuri, Principal
Architect, Abin Design Studio

One of the foremost talents in the realm of Indian architecture, Reza Kabul’s foray into the industry was a random experience of viewing books on architecture that proved catalyst enough for a switch from engineering to architecture. After a brief stint at a prominent architecture studio in Mumbai, he set up ARK – Reza Kabul Architects Pvt. Ltd., India in 1988. Reza Kabul has envisioned and successfully executed a string of path breaking projects cantered on the design philosophy of ‘liberating spaces’. He has handled projects for leading names in Indian real estate industry, and continues to enjoy the trust and appreciation with projects that set pioneering benchmarks in architectural design. A speaker for ‘Marcus Evans Tall Buildings Conference’ in Seoul, Korea (2008) and a pioneer in tall buildings, Reza Kabul has been listed in the Limca Book of Awards (2003) for Shreepati Arcade, the tallest building in India. His signature projects are spread globally in United States, India, Mauritius, United Arab Emirates, Sri Lanka, Sudan, Bhutan, Korea, and Nairobi.

Curtain WallThe curtain wall concept is implemented in the façade design of Altitude

The proposed 383m tower, Altitude, will be 211m taller than the current tallest building – World Trade Center – at Colombo, Sri Lanka. This mixed-use high-rise development, is planned as a revenue-generating landmark structure that shall mark Sri Lanka’s presence on the world map of high-rises. The skyscraper will incorporate various private and public spaces including luxurious apartments and penthouses, retail and commercial spaces, a revolving speciality restaurant, an indoor cricket training facility, and a 360degree observatory.

Wind AnalysisFig.1. Wind Rose Diagram for the Entire Year
Solor AnalysisFig.2. Solar Path Diagram for the Entire Year


The curtain wall concept is implemented in the façade design of Altitude, amounting to an approximate of 1, 10, 000 Sq m of glazing area. The research below traces the underlying decision that led to the development of the overall curtain wall concept; focusing on the design options at different location on the exterior, and also on the intricacies of the design.


Entrance: The external façade is of aluminium vertical post with stainless steel patch fittings for the shop front areas. Laminated glass units have been used considering safety of occupants. Two frameless automatic sliding doors are used for entry and exit of commercial areas with an entrance canopy of 9 m.

Podium: The podium levels include the commercial and parking area which incorporate the Di-Grid arrangement using capped curtain wall concept spanning. A combination of reflective double glass units and reflective stainless steel / aluminum panels are used for aesthetic value. There is no glass closure for parking area to facilitate the water cooling arrangement behind curtain wall.

Bat Levels: The bat levels are Level 15 to 65. It uses the inclined unitized curtain wall concept for the entire façade closure of 51 levels. A corner arrangement is provided for connecting the inclined glazing with the straight glazing on the sides. A 4 hour fire rating arrangement is provided with
parallel open-able windows for 30 per cent better ventilation. 10 per cent of total façade vision area are parallel open-able windows as per norms. Castin anchor channels are to be used for installing the unitized systems.

Handle Levels: The handle levels are Level 67 to 91 which are in the shape of the handle of the bat. It uses the inclined unitized curtain wall concept for the entire façade closure of 25 levels. External fins on all levels of the handle areas mimic the rubber rim on a cricket bat handle.

Ar. Reza KabulThe Sky Deck on Level 16

Deck Levels: The Entertainment Deck on Level 14 and the Sky Deck on Level 16 incorporate 2 m high aluminum and glass balustrades with laminated sentry glass for safety of the occupants. Clear glass is used for continuous vision.

Observatory Level: The Observatory level at height of 350 m incorporates a 3 m high aluminum and glass balustrades with laminated sentry glass. Clear laminated double glass units in spider glazing are used. Spider glazing façade is used for observatory lobby to allow continuous exterior vision.

Dome Level: The dome hosts the Indoor Cricket Academy on Level 96. A stainless steel structural grid supports the 54 m diameter façade enclosure. The façade incorporates a combination of glass and photovoltaic panels for achieving the concept self energy generation. Laminated double glass units are used for safety of players.

Bird’s eyeBird’s eye view of the project


Reinforced Cement Concrete (RCC) is adopted for the design of all structural members of altitude. The environmental exposure condition for the structure is taken as ‘Extreme’ ensuring minimum Cement Content as per codal requirements.


Altitude is designed as an all reinforced concrete structure with high grade concrete in combination with high grade steel right from the foundation to Level 96, and is topped with a structural steel braced frame to support the glass facade. The structural framing system is designed as a combination of ductile shear walls with ordinary moment resisting frames. The lateral loads which are acting on each floor are shared by beams, shear walls, columns & floor diaphragms. Linear static analysis has been carried out for this structure.

The Structure is subjected to 3D frame analysis wherein the various parameters for the stability and serviceability of the structure under
service loads including drift, deflection, torsion effects, and soft storey effects are ascertained and complied with the codal requirements. The Beams are designed for the critical bending moments and shear forces for various load combinations under service loads. Columns are designed for axial loads, lateral loads, biaxial moments resulting due to frame moments including wind and seismic forces, slenderness effects and eccentricities.


Project: Altitude
Location: Colombo, Sri Lanka
Architect: ARK Reza Kabul Architects Pvt. Ltd.
Client: Shreepati’s Edifice Pvt. Ltd., Wills Realtors, & VIVANTA Associates
Area: 26,274 sq m
Height: 383 m
Stories: 96
Status: Under Construction