Sustonable announces equity investment from Gülermak Heavy Industries


Press Release

Sustonable announces equity investment from Gülermak Heavy Industries

Amsterdam, Valencia and Ankara – 18 February 2020 – Gülermak Heavy Industries, through its strategic investment group Shibumi International, has closed an investment in Sustonable, a sustainable building materials company which produces composite stone surfaces. The substantial investment allows Sustonable to begin large-scale production and move into the global marketplace.

Building a new factory

With this new investment, Sustonable is now installing the first large-scale production line in Polatli, Turkey, southwest of Ankara, with the support of Gülermak. This production line has the capacity to produce several hundred thousand square meters of material per year. Sustonable is now setting up the distribution network and infrastructure required to service its launching customers.

Sustonable specializes in the patented production process of composite stone surface material, utilizing a fully recycled binding agent (recycled PET) from plastic bottles which accounts for most of the material. Recycled PET can be used in a broad range of commercial, residential and built environment applications.

Sustonable initially will manufacture high quality kitchen countertops with the look and feel of natural stone to service kitchen suppliers. In addition, Sustonable will manufacture tabletops and shower wall panels to resellers.

Sustonable will expand operations in research and development and marketing and sales in Spain and the Netherlands, focusing on improving the product and developing new applications for external uses. In addition, Sustonable will grow the operations in Turkey with an eye toward opening additional facilities in the near future.

Technical works under way

The investment round closed in January. The final installation of equipment and production lines at the new factory began last September and is ongoing. Sustonable is accelerating work so production can begin as soon as possible and no later than early summer.

Innovative material

The technology and product composition is unique and patented.

Recycled PET – plastic bottles made from polyethylene terephthalate – is processed into a synthetic fiber that is highly suitable for recycling and is used as a binding agent. This material is 100 percent recyclable, which contributes to the circular economy.

Sustonable’s process eliminates the need for natural stone by as much as 80 percent, transforming plastic waste from our oceans into high quality new products for homes.

Sustonable’s first product line will be used for countertops, table tops and wall panels for bathrooms, offering endless opportunities for interior design. The material has the appearance of natural stone but is less costly to produce. This innovative surface material uses up to 50 percent fewer natural resources and is lighter, more flexible, and durable than existing materials.


Gülermak Heavy Industries Construction & Contracting Co. Inc. is a sixty-year-old company active in construction and contracting of industrial, infrastructure and transportation projects. Gülermak is a leading steel fabricator in Turkey, serving diverse clients in more than 30 countries.

Gülermak identifies sustainability as a core challenge of the future and is proud to invest in Sustonable. Gülermak brings its manufacturing expertise to a company committed to contributing to a more sustainable future.

Shibumi International, a wholly owned subsidiary of Gulermak, focuses on innovative projects in the built environment such as construction, facilities management, building inspection, and innovative solutions to urban life. At its core, Shibumi is dedicated to helping Gülermak diversify as the company evolves beyond its 60th year.

The investment further strengthens the collaboration with our existing partners:

  • Dekker Groep is the largest manufacturer of countertops in Europe, with activities in the Netherlands, Belgium, Germany, Sweden and Norway. Dekker Groep contributes sophisticated market intelligence and fabrication technology about the countertop market. The firm also has developed the most modern and advanced production systems in the world for processing quartz composite materials into countertops.
  • SUEZ (Paris: SEV, Brussels: SEVB) is a multinational firm with world-wide knowledge of the circular economy and access to global PET resources. With more than 82,000 employees, SUEZ has operations on all five continents, making it a key player in the circular economy for sustainable management of resources. Global revenue for 2017 was 18.2 billion dollars.
  • HighTechXL, a deep-tech venture-building accelerator based at the High Tech Campus in Eindhoven, The Netherlands, builds teams of entrepreneurs and tech talents around the most advanced technology in the world in partnership with CERN, TNO, Philips and other global innovators. HighTechXL leads corporate innovation programs with multinationals in Europe and China, helping them become faster, leaner and more competitive.

About Sustonable

Sustonable was founded by Erik Schoneveld, Laurens van Graafeiland and Aad van Helden in 2014. Sustonable is headquartered in Amsterdam with 15 employees in total and has operations in Spain and Turkey.

Would you like to know more?


Laurens van Graafeiland, CFO

+ 31 6 285 651 75Ivangraafeiland@sustonable.com