History

1935
Carl Wilhelm Cleff establishes a company in Wuppertal, that produces ledges and fittings which are used for the fitting of vehicles and in the shop fitting sector. His idea: the award-winning development and marketing of products of high quality.

1936 - 1945
The demand for high-quality products was high. The company develops quickly, new employees are being hired; the production area is expanded. Carl Wilhelm Cleff, an entrepreneur full of ideas, inspiration and energy, supports his employees and builds a strong community.

1946 – 1955
The war doesn´t fail to leave its marks on Cleff, but the new beginning succeeds quickly. After the rebuilding, the company is able to establish international contacts. The global increasing of the private transport sector in the 50s  leads to a significant growth of buses and trains, that enhances the demand of vehicle-windows.

1956 – 1965
A whole generation is about to change. It seems that times of economic success are about to come – and that is exactly the goal Cleff is working on by that time. The product range of vehicle-windows is being expanded by engine-room-, access-, and divider-doors. The window construction is developing more and more sophisticated and comfortable solutions, such as slide- and cover- windows for instance. That leads to a fully developed product portfolio, which is available and constantly advanced.

1966 – 1980
The enterprise is growing dynamically, buys property and builds new manufacturing plants. It remains true to Wuppertal, Germany and its´ people. Investments are being realized wisely, amongst others into development. Several patents are brought forward collectively. Thanks to the talent and the know-how of the staff regarding the construction of vehicle-windows, Cleff is able to explore the international market of rail- and commercial vehicles of every kind on a sustainable basis.

1981  - 2000
Regarding the construction of the “solar tower” as well as new halls equipped with solar systems, Cleff´s supervisors count on the use of solar power. This, as well as others measures were and still are part of the company´s philosophy that counts on high efficiency in harmony with nature and environment. 
Successfully: Vehicle windows, machinery room and divider-doors are meanwhile used in 25 nations. They offer complex slide- and cover-mechanisms, comfort and safety. Innovation potential is showing up when it comes to future oriented projects like the window development of the Lirex experimental-train or several versions of the Flush-window, that combines technical demand and comfort. New ideas as well as the pursuit of the own development  have influence on the brand Cleff – yesterday as well as today.

Since 2014
In order to constantly advance the with the own development, Carl Wilhelm Cleff is put through an extensive reorganization by the supervisors in charge. After a deep “Status-Quo-Analysis”,
the production process is being modified and products are updated. That leads to an improvement of the cost structure and thus to better profitability and flexibility. The reorganization enables an attractive price structure, that can be directly adapted to the clients of Cleff. That leads to a strong position of the company on a highly competitive global market.

2016 – 2020
Based on the reorganization that was established in 2014, the company is doing well. By consolidating their efforts, the employees are able to gain several new projects in the manufacturing area of railway and specialized vehicles, which are equipped with
innovative solutions of doors and windows. New customers were acquired and several new projects successfully brought to a close. The company did not shy away from any challenge and took on new and even more technically demanding tasks. Small and large quantities were manufactured. We devoted much attention to niche markets, thus making it possible to manufacture windows for excursion ships and nostalgia trains. A particularly prestigious project was the sophisticated window construction for the Wuppertal suspension railway, with which the municipal utilities organisation entrusted the traditional manufacturer. With its system solutions, Cleff provides end-to-end systems that set the trend for tomorrow‘s markets. For vehicle doors, this means the complete implementation of a complex door system with frame, seals, lock, door and window mechanics. System solutions for vehicle windows also often require a special handle mechanism. „Everything from a single source“ has become a matter of course for the window and door experts at Cleff.

2021 – 2023
Now, Cleff does not only stand for modern window solutions, but also increasingly for the development of complex door systems. Areas have been opened up again, for example Cleff finds new access to the market in the area of ship windows. Current crises promoted innovative projects: in 2020/21, Cleff equipped approx. 4.000 driver workplaces with 100 different self-developed glass driver protection systems. This made public transport buses future-proof and economical in terms of safety and hygiene during the COVID-19 pandemic. The Cleff company has prepared itself for the future. With an expansion of the workforce, preparation for upcoming generational changes, and new plants and machines ... Regular customer satisfaction surveys reveal potential for improvement. But they also show that now more than ever, the Cleff brand embodies customer orientation and reliability. The focus is on the customer – here, his requirements and wishes are taken care of. And that quickly and without any complications.

Environmental protection – conservation of resources
Innovative LED lighting concepts, energy-saving machines, more efficient air purification systems and a 3,145 m² photovoltaic system ... These are all measures for the great challenges of the future. In 2022/23, the company developed all roof surfaces for the use of solarenergy. Now, almost 1.700 solar modules ensure a CO² saving of almost 250.000 kg per year. This can cover the annual electricity consumption of 176 households.
The mobility transition is in full swing. Increased environmental awareness and the renunciation from inner-city individual transport are supporting the growth of local public transport, increasing its quality and the size of vehicle fleets on road and rail. Cleff accompanies this trend with its products in the initial equipment and refurbishment of older vehicles.

The company today
The company no longer stands only for the development of vehicle windows but also for the development of complex door systems and partition walls.As in window construction, the company has developed further with numerous projects and has made a name for itself in these areas as a recognised system supplier. The ultra-modern test centre provides an additional range of services. And the extensive range of spare parts in the „Spare Parts Competence Centre“ offers interesting prospects for numerous vehicle operators, as it enables the refurbishing of vehicles at the highest level. Today, Cleff is more than ever focused on the essentials: as a modern company with environmentally-oriented, energy-efficient plants and flat hierarchies, it creates customer-oriented solutions. Thinking under the sign of the Cleff rhomb is service-oriented and the modern production guarantees the flexible production of high-quality window and door solutions for a wide variety of vehicles. Cleff offers direct communication, quality, fair prices and reliability. The brand „Cleff“ is well positioned for tomorrow‘s markets.