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Window & Door
Fabrication


At Complete Window Systems Ltd, we take pride in a manufacturing process that reflects the same values we’ve upheld since 1986: quality, precision, and genuine craftsmanship. Our factory may be small, but it is highly efficient, allowing us to maintain close control over every stage of production and ensure that every window meets our exacting standards.

Our Manufacturing Process

​Creating a high‑quality uPVC window or door is a detailed, multi‑stage process that blends precision engineering with skilled craftsmanship. Here’s a clear overview of how we turn raw uPVC profiles into the finished products that leave our factory.

 

1. Profile Cutting
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Every window or door begins with long lengths of uPVC profile. These are measured and cut to size using specialised machinery to ensure perfect accuracy. Even the smallest deviation can affect the final fit, so precision at this stage is essential.

 

2. Reinforcement, Thermal Inserts & Drainage Preparation
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Once the profiles are cut, we prepare them for strength, performance, and long‑term reliability.

  • Steel or aluminium reinforcement is inserted into the profiles to provide structural stability, especially for larger frames and doors.

  • Thermal reinforcing inserts can be added where required to improve energy efficiency and overall thermal performance.

  • Drainage pathways are created at this stage, ensuring that any water entering the frame can exit safely and efficiently.

 

This combination of reinforcement, thermal optimisation, and drainage preparation forms the backbone of a strong, reliable window or door.

 

3. Welding or Mechanical Jointing
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The prepared profiles are then joined to form the frame or sash.


Depending on the design and customer preference, this can be done using:

  • Fully welded joints — corners are heated and fused for a seamless, modern finish.

  • Mechanical joints — ideal for traditional or heritage‑style windows, offering a classic appearance with modern performance.

 

Both methods deliver strength and longevity.

 

4. Cleaning & Finishing
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After welding or assembly, the corners are cleaned and finished.
If welded cills are requested, they are polished at this stage to achieve a smooth, professional look.

 

5. Hardware & Component Fitting
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Next, all essential components are installed, including:

  • Hinges

  • Locks

  • Handles

  • Gaskets

 

This ensures smooth operation, secure locking, and proper sealing.

 

6. Glazing Preparation
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We offer a wide range of glazing options to suit different needs, including:

  • Double glazing

  • Triple glazing

  • Acoustic glazing

 

Glass units are prepared and matched to the correct frame type — whether internally glazed or externally glazed — to help match existing windows or meet specific design requirements.

 

7. Pre‑Assembly of Bays & Combinations
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For bay windows and combination frames, we fully pre‑assemble them in‑house.
This allows us to check:

  • Alignment

  • Angles

  • Structural accuracy

 

Where required or requested, bay jacks are pre‑installed to ensure the bay is correctly supported and ready for installation on site.

 

8. Final Quality Checks

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Every window and door undergoes a thorough inspection. We check:

  • Operation

  • Finish

  • Alignment

  • Seals

  • Hardware function

  • Overall build quality

 

Nothing leaves our factory unless it meets our standards.

 

9. Ready for Delivery or Collection

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Once approved, the finished product is prepared for delivery or collection.
Customers are welcome to visit our factory by appointment to see the process in person and view products at different stages of manufacturing.

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