GEN-TES Eng. Co.Ltd. was established in Ankara/Turkiye by Mechanical Engineer Fatma Colasan in January 1979, and later Mechanical Engineer Aziz Inac joined GEN-TES as a partner. The Company renders Mechanical Engineering design and design consultancy services, preparation of technical specifications and site supervision of mechanical works under construction.

Additionally, in the year 1990, the multi-disciplinary Engineering & Architecture company ODTM Engineering Consultancy Co. Inc. was established as a ‘mother company’, partners of which were Fatma Colasan and Aziz Inac (partners of GEN-TES Eng. Co. Ltd.), Taylan Karabey (owner of ‘Taylan Karabey Civil Eng.Co.), Kaya Konuray  (owner of ‘Konuray Architectural Firm’) and Engin Alsac (owner of ‘ENERTES Elect.Eng. Co. Ltd.). After the establishment of ODTM, GEN-TES undertook the Mech. Eng. design and site supervision services of all the projects which were rendered through ODTM, in addition to the services of GEN-TES which were provided independently.

Upon the loss of two partners of ODTM (Mech. Eng. Aziz Inac and Elect.Eng. Engin Alsac) during a car accident in the year 2000, the mother company ODTM continued its activities until the year 2014, after which it was closed. Between the years 2000-2014, GEN-TES also undertook Electrical Engineering design services upon Electrical-Electronics Engineer Mehmet Colasan’s joining GEN-TES as a partner. Starting from the year 2014, GEN-TES also added Contract Consultancy, Claim Management, DAB (Dispute Adjudication) and DAAB (Dispute Avoidance/Adjudication) services to its working field as related to construction works, which are implemented mostly through FIDIC Conditions of Contracts.

At present, GEN-TES continues providing Mechanical Engineering design & design consultancy, preparation of technical specifications and construction supervision services, plus DAB/DAAB (Dispute Adjudication & Dispute Avoidance/Adjudication\ ), Construction Contract Consultancy, Claim Management services as indicated above.

Scope of Mechanical Engineering design and design consultancy services:
– Heating, ventilation, air conditioning (HVAC)
– Refrigeration 
– Drying processes 
– Energy conservation and heat recovery 
– Central heating and cooling plants 
– Condensation control 
– Swimming Pool , Bath and Pond designs
– Automatic controls and BMS (Building Management System) 
– Hot & cold domestic water, drainage & storm water, sterile water 
– Central sterilization 
– Piped medical gases, vacuum & pressurized air 
– High & low pressure steam
– Solar energy  
– Fire prevention and extinguishing 
– Smoke exhaust & pressurization 
– Water filtering & softening 

Scope of Electrical Engineering design and design consultancy services:  
– Low voltage (interior-exterior lighting, power and socket, energy distribution for mech. equipments, grounding, lightning, generator, UPS)
– Weak current (data, telephone, TV and satellite TV, fire detection & alarm, dubbing-announcement broadcast, security installations, CCTV, card access)
– Transformers
– Medium voltage lines
– Lifts 

Later added services (2007-present)
Contract Consultancy, Claim Management, Dispute Avoidance/Adjudication and Dispute Adjudication services of construction works which are implemented through FIDIC Construction Contracts and similar, and which are mostly financed by IFIs (International Financing Institutions) such as IBRD, EBRD, ADB etc

Scope of DAB/DAAB services (2014-present)
Contract Consultancy, Claim Management, Dispute Avoidance/Adjudication and Dispute Adjudication services of construction works which are implemented through FIDIC Construction Contracts and similar, and which are mostly financed by IFIs (International Financing Institutions) such as IBRD, EBRD, ADB etc. .

GEN-TES provides its clients with high quality Engineering services. Through its mother company ODTM (1990-2014), the group is accepted to the FIDIC Business Integrity Management System – Pilot Program. *
Among the Engineering Consultancy services which are completed by GEN-TES until  present are mainly mix-use facilities, health-care facilities, high-ranking hotels, office buildings & business centers, shopping malls, conference-culture-arts buildings, administrative buildings, banks, educational facilities, industrial facilities, social-recreational and sports facilities, commercial buildings, airport facilities including terminals, central heating-cooling plants & exterior networks, accommodations & dwellings, swimming pools- ponds & baths, laboratories,  and similar.

GEN-TES became a member of MERGE Consultants in the year 1999, which is a business cooperation group of Engineering Consultancy Companies in Europe, and which welcomes only two  member firms from each European country. GEN-TES has acquired a high level of knowledge and experience in international Engineering Consultancy procedures through its Managing Director’s continuous voluntary involvement in FIDIC** since the year 1992and in EFCA*** since the year 2002. 

In the year 2023, GEN-TES Eng. Co. Ltd. &DOLFEN Eng. Co. Inc. signed a permanent Agreement to cooperate on international projects, having the Partnership logo as GTDP, referring to Gen-Tes & Dolfen Partnership to render international Engineering Consultancy Services together.

Contact details of GTDP and its partner companies are given below:

GEN-TES:
Website:  www.gen-tes.com.tr  E-mail: info@gen-tes.com.tr Tel: +90(532)615 9060
Address: Ugur Mumcunun  Sokak No: 9/6 GOP 06700 Cankaya Ankara TR

DOLFEN:
Website:  www.dolfen.com E-mail : info@dolfen.com  Tel: +90(312)468 59 30
Address: Uskup Cad. (Cevre Sokak) No. 20/3 Kavaklidere 06680 Cankaya Ankara TR

GEN-TES & DOLFEN PARTNERSHIP:
Website: Websites of GEN-TES & DOLFEN (above)
E-mail & Tel: E-mail addresses and phone numbers of partners given above

* The relevant pilot program which is referred to above has been applied in eight countries and ODTM, (together with GEN-TES) was one of the two companies invited from Turkiye.
** FIDIC – International Federation of Consulting Engineers (Established in Ghent/Belgium in the year 1913, the current headquarters being in Geneva/Switzerland.)
*** EFCA – European Federation of Engineering Consultancy Associations (Established in Amsterdam/Netherlands in the year 1992, current headquarters being in Brussels/Belgium.)