Manufacture of windows, doors and sliding systems made of PVC and aluminium for the trade
DeKa Kunststoffenster GmbH
Bielefeld (Jöllenbeck), Heidsieker Heide 28New on Amplifa
This is us
DeKa Kunststoffenster GmbH is a medium-sized family company based in the Bielefeld district of Jöllenbeck. Since 1976, the company has been producing windows, doors and sliding systems made of PVC and aluminium, including PVC windows, aluminium windows, entrance doors, secondary entrance doors, lift-and-slide doors and folding systems. Production is based on Schüco profile systems and Winkhaus hardware; production begins in-house with cutting and also includes special shapes such as angled elements, round arches, corner-over-corner glazing and PSK (tilt-and-slide) elements. Thermal insulation glazing, sound insulation glass, laminated safety glass (VSG) and glazing with argon gas filling are used. The sales channels are specialised dealers in Germany, Austria, France, the Netherlands, Belgium and Luxembourg; logistics and installation services are handled through the company's own resources or through the trade. The company operates a quality management system in accordance with DIN EN ISO 9001:2015, RAL internal and external monitoring, and factory production control (WPK).
- Site
- Bielefeld
- Processes
- Window production from PVC (PVC windows), Window production from aluminium, Manufacturing lift-and-slide doors from PVC, Manufacturing aluminium sliding systems (lift-and-slide doors, folding systems, room dividers), Manufacturing doors from PVC (entrance door, secondary entrance door), Manufacturing doors from aluminium (entrance door, secondary entrance door), Special shapes and special designs (angled elements, round arches, corner-over-corner glazing, PSK, Cutting (production starting from cutting)
- Materials
- PVC profiles, Aluminium, Thermal insulation glass, Sound insulation glass, Laminated safety glass (VSG), EPDM, Aluminium cladding shell (finishing), Argon (gas filling)
- Certificates
- DIN EN ISO 9001:2015, RAL monitoring, Factory production control (WPK)
- Founded
- 1976
- Industries
- Construction sector/window and door manufacturing, Residential construction, Commercial construction
- 01
Cutting
- 02
Manufacture of windows/doors/sliding systems (PVC and aluminium)
- 03
Glazing
- 04
Factory production control (WPK)
- 05
In-house logistics
- 06
Installation by DeKa specialised dealers
Materials and systems
PVC profiles
High-quality Schüco PVC profiles for windows, doors and lift-and-slide doors with high thermal insulation.
Aluminium
For slim frame appearances, high stability and low-maintenance windows, doors and sliding systems.
Aluminium cladding shell (finishing)
Exterior finishing of PVC windows for protection and additional stability.
Thermal insulation glass
Reduces heat transmission and lowers heating energy requirements.
Sound insulation glass
Asymmetric construction with sound insulation gas filling, sound reduction up to 45 dB.
Laminated safety glass (VSG)
Burglary-resistant glass according to DIN EN 356 in classes P2A, P4A and P5A.
EPDM seals
Functional seals on PVC profiles for high weathertightness.
Argon gas filling
Gas filling of the pane cavity to improve thermal insulation.
Site
Bielefeld (Jöllenbeck)
DEProduction and administration site
- Materials
- PVC, aluminium, glass
- Modern production lines for window manufacturing (acquired 2014)
- Own vehicle fleet
Industries
Processes & technical limits
| Processes | Tolerance | Max. part | Weight | Lot size | Materials |
|---|---|---|---|---|---|
| Window production from PVC (PVC windows)Joining | – | – | – | – | PVC profiles, Glass |
| Window production from aluminiumJoining | – | – | – | – | Aluminium |
| Manufacturing lift-and-slide doors from PVCJoining | – | – | – | – | PVC profiles, Glass |
| Manufacturing aluminium sliding systems (lift-and-slide doors, folding systems, room dividers)Joining | – | – | – | – | Aluminium, Glass |
| Manufacturing doors from PVC (entrance door, secondary entrance door)Joining | – | – | – | – | PVC profiles, Glass |
| Manufacturing doors from aluminium (entrance door, secondary entrance door)Joining | – | – | – | – | Aluminium, Glass |
| Special shapes and special designs (angled elements, round arches, corner-over-corner glazing, PSKJoining | – | – | – | – | PVC profiles, Glass |
| Cutting (production starting from cutting)Machining | – | – | – | – | PVC profiles, Aluminium |
1 Anlagen & Maschinen
| Machine | Manufacturer / model | Quantity | Working area | Year built | Site |
|---|---|---|---|---|---|
| Production line (window manufacturing) | – | – | – | 2014 | Bielefeld-Jöllenbeck |
Additional services
Quality
Quality is ensured by a quality management system in accordance with DIN EN ISO 9001:2015, consistent internal and external monitoring according to RAL, and factory production control (WPK).
| Evidence | Bielefeld (Jöllenbeck) |
|---|---|
| DIN EN ISO 9001:2015 | |
| RAL monitoring | |
| Factory production control (WPK) |
History
- 1976
Founded by Manfred Diekmann and Gerhard Kämper in Bielefeld-Heepen; start of window production with manufacturing and own installation
- 1989
Relocation to Bielefeld-Brake; management taken over by Thomas Diekmann; definition of the sales strategy via resellers
- 1998
Relocation to Bielefeld-Jöllenbeck; investment of over 7 million € in the production and administration building; expansion of the own vehicle fleet
- 2000
Expansion of the production area to 6000 sqm; first trade fair participation and first website
- 2012
Modernisation of the administration wing; purchase of additional usable space
- 2014
Construction of a production hall extension; acquisition of state-of-the-art production lines
- 2022
Marco Diekmann takes over sole management in the third generation, supported by Christian Diekmann
- 2025
Restructuring and reorganisation of the administration
- 2026
50 years of DeKa – anniversary celebration at the Lokschuppen Bielefeld