Located in the capital city of Ankara, the Turkish Contractor’s Association HQ (TCA) is designed on sustainable principles from the ground up, and intends to send a clear, future-oriented message from the Turkish building industry to the world at large. From Turkey’s first modern underground labyrinth for passive air conditioning, to the meticulously designed shading on the facade, the building speaks volumes about the possibility of feasible, effective, and collaboratively-designed sustainable systems. It is an architectural image that stands on the global stage.


Turkish Contractor’s Association




Turkey, Ankara


2011 – 2013


The project was the result of a limited design competition, with a brief that placed a great emphasis on leading environmental design approaches. From the outset the project team was a multidisciplinary group, both international and local, which included Atelier Ten from London as environmental engineers. The completed building received LEED Platinum Certificate and is already regarded as a showcase of leading edge environmental design, which has raised the bar for designers and clients alike, not only in Ankara but the whole of Turkey.


1. Hot air in external environment goes from stacks into the labyrinth.
2. Hot air cools down naturally as it covers distance inside the labyrinth.
3. Air losing its heat reaches air conditioning stations according to conditions, if necessary it is further cooled down.
4. Air going through canals embedded in R/C slabs also cooling concrete mass reaches cold beams.
5. Cold beam depending on the need in the environment further cools down the air, releasing it into the interior.
6. Air heated up due to the impact of machines and people is collected in ventilation ducts and carried to heat recovery units.
7. The atrium at the core of the building with stack effect collects all heated air at the highest level, carrying it to heat recovery stations, again through ducts.
8. Thanks to the mesh and shade elements forming the exterior of the building, heat recovery is minimized.
9. There are also hot air pipes and photo-voltaic panels on the roof.




Avciarchitects TMB Sustainability Awards


Architectural Team
Competition Project Design Team

Selçuk Avcı, Burak Ünder, Buşra Al, Markus Lehto

Architectural Practice Project Design Team

Selçuk Avcı, Burak Ünder, Tayfun Aksoy, Büşra Al, Begüm Tırpancı, Ufuk Berberoğlu, Cem Fırat Bayır, Berkin Lale, Berkan Çelik, Atılım Yılmaz

Architectural Project Controller Team

Selçuk Avcı, Burak Ünder, Deniz Nar, Begüm Tırpancı, Buşra Al, Tuğba Öztürk, Hürsel Sarıdağ

Other Consultants
Project Management and Construction Controller

IMS Mühendislik Danışmanlık

Sustainability Consultant

Atelier Ten

Interior Architect


Landscape Architect

Arzu Nuhoğlu Peyzaj Tasarım

Contractor Company

Mesa Mesken Sanayii

Structural Engineer

Ural Mühendislik

Mechanical Engineer

Okutan Mühendislik

Electrical Engineer

Yurdakul Elektrik

Retaining Structure Engineer

İksa Mühendislik

Infrastructure Engineer

Kadim Mühendislik

Fire Protection Engineer

Karina Tasarım

Acoustic Engineer

Mezzo Tasarım

LEED Consultant

TURKECO İnşaat ve Enerji Ltd. Şti.

Signage Design

Murat Dorkip




Yunus Özkazanç