Al Mass Tower
Height 138 m / 453 ft
Floors 31
Official Name

The current legal building name.

Al Mass Tower

CTBUH collects data on two major types of tall structures: 'Buildings' and 'Telecommunications / Observation Towers.' A 'Building' is a structure where at least 50% of the height is occupied by usable floor area. A 'Telecommunications / Observation Tower' is a structure where less than 50% of the structure's height is occupied by usable floor area. Only 'Buildings' are eligible for the CTBUH 'Tallest Buildings' lists.

Architecturally Topped Out
Structurally Topped Out
Under Construction
On Hold
Never Completed
Competition Entry
Proposed Renovation
Under Renovation
Under Demolition
Completed, 2003

The CTBUH follows the United Nations's definition of Country, and thus uses the lists and codes established by that organization.


The CTBUH follows the United Nations's definition of City, and thus uses the lists and codes established by that organization.


A single-function tall building is defined as one where 85% or more of its usable floor area is dedicated to a single usage. Thus a building with 90% office floor area would be said to be an "office" building, irrespective of other minor functions it may also contain.

A mixed-use tall building contains two or more functions (or uses), where each of the functions occupy a significant proportion of the tower's total space. Support areas such as car parks and mechanical plant space do not constitute mixed-use functions. Functions are denoted on CTBUH "Tallest Building" lists in descending order, e.g., "hotel/office" indicates hotel function above office function.

Structural Material

Both the main vertical/lateral structural elements and the floor spanning systems are constructed from steel. Note that a building of steel construction with a floor system of concrete planks or concrete slab on top of steel beams is still considered a “steel” structure as the concrete elements are not acting as the primary structure.

Reinforced Concrete
Both the main vertical/lateral structural elements and the floor spanning systems are constructed from concrete which has been cast in place and utilizes steel reinforcement bars.

Precast Concrete
Both the main vertical/lateral structural elements and the floor spanning system are constructed from steel reinforced concrete which has been precast as individual components and assembled together on-site.

Utilizes distinct systems (e.g. steel, concrete, timber), one on top of the other. For example, a steel/concrete indicates a steel structural system located on top of a concrete structural system, with the opposite true of concrete/steel.

A combination of materials (e.g. steel, concrete, timber) are used together in the main structural elements. Examples include buildings which utilize: steel columns with a floor system of reinforced concrete beams; a steel frame system with a concrete core; concrete-encased steel columns; concrete-filled steel tubes; etc. Where known, the CTBUH database breaks out the materials used in a composite building’s core, columns, and floor spanning separately.


Height is measured from the level of the lowest, significant, open-air, pedestrian entrance to the architectural top of the building, including spires, but not including antennae, signage, flag poles or other functional-technical equipment. This measurement is the most widely utilized and is employed to define the Council on Tall Buildings and Urban Habitat (CTBUH) rankings of the "World's Tallest Buildings."

138 m / 453 ft
To Tip
138 m / 453 ft
Floors Above Ground

The number of floors above ground should include the ground floor level and be the number of main floors above ground, including any significant mezzanine floors and major mechanical plant floors. Mechanical mezzanines should not be included if they have a significantly smaller floor area than the major floors below. Similarly, mechanical penthouses or plant rooms protruding above the general roof area should not be counted. Note: CTBUH floor counts may differ from published accounts, as it is common in some regions of the world for certain floor levels not to be included (e.g., the level 4, 14, 24, etc. in Hong Kong).

Construction Schedule

Construction Start



Structural Engineer
Nasa Multiplex

About Al Mass Tower

Al Mas, meaning “diamond” in Arabic, is essentially two towers which overlap along their east–west axis. As the venue for the Dubai Diamond Exchange, the Al Mas Tower is distinctively styled as the centerpiece of the city’s Jumeirah Lakes development. Two interlocking elliptical towers with office accommodation on 53 floors gently taper as they ascend, rising to a mast at the summit.

The two towers respond differently to their orientation. High performance externally treated insulated panels protect the south facing tower while the north facing tower employs more transparent glass allowing the benefit of the cooler ambient light, as well as being shaded by the taller insulated tower. At the base of this slender superstructure is a two-story steel podium in the form of eight shards of glass inspired by the glittering facets of a cut diamond. Radiating from the central core and corresponding to the principal points of the compass, the triangles reflect the surrounding water and animate the façade. The diamond exchange center, the largest in the Middle East, is located in the largest of the triangular spaces and cantilevers out over the lake. The space also includes a generous roof lantern allowing daylight to illuminate the trading floor and facilitate expert diamond inspection and trading. The podium glass is of a specification such that the diamond inspection process will not be influenced by the refracted light.

The vertical core was optimized at the design phase, with two independent vertical transport engineers exploring 27 different core configurations to eventually achieve an 80.1% core efficiency on the 1,600 square meter (17,200 sq ft) floor plate over the 68 floors. This efficiency, with a maximum average waiting time of 42 seconds, had not been achieved on commercial buildings of this height.

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