Unique slide and fold dual hollow aluminium system. The doors which sit in a rebated frame have an external curved shape with internal beading. Bottom wheels and top glider are safely concealed within a dedicated floating mullion with the door leafs being joined by a butt type knuckle hinge. Suitable for domestic and light / medium / heavy duty commercial applications.

Easy access low threshold accessibility option.

Visofold 4000 bi-folding door profile

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Product Information


The folding door system with thermal break allows you to create large passages.

The system is built up using a frame in which moveable parts or elements are placed in such a way that it is possible to fold the elements to the left or right.

These elements or sashes are supported and hinged to a mullion.

At the bottom the mullion is supported by a roller mechanism which slides along the sill profile while at the top, the mullion is guided by another roller mechanism.
There are several possible combinations of elements and opening sashes.


  • This series of folding doors is mostly used in hotels and restaurants, stores and in private houses, in order to open a complete wall to create a larger space in the summer.
  • The system is also interesting for conservatories to use as a screen you can open completely in summer times.


  • Extruded out of aluminium-alloy AlMgSi 0,5 F22 according to DIN 1725.
  • Tolerance according to DIN17618.


  • Electrostatic powder coating: according to the guidelines of APA-Qualicoat in most of the current RAL-colours.
  • Possible to colour in wood structure to imitate different woods (Powder coated according to Qualicoat). All coatings will be delivered with a certificate of guarantee for 15 years.
  • Anodisation: in satin or bronze colours with E.E.W.A./EURAS-Qualanod quality label.
  • Thermal break: The profiles consist of 2 aluminium extrusions which are separated from one another by polyamide strips PA 6.6.25 reinforced with glass fibre. A gluing thread, rolled and pushed in together with the thermal break profile, ensures a strong adhesion after melting and flowing, when the profiles are heated in the hardening furnace.


  • Built-in depth: outer frame 78 mm, sash 70 mm.
  • Sealings: with extruded EPDM rubbers and PP-brushes
  • Glazing: from 4 to 37 mm.
  • k-value: 3.11 W/m²K
  • Hardware: EUROGROOVE
  • A large amount of combinations is possible with or without a walk-through door.
  • Choice between a high or low sill profile. The low one allows you to level out the frame with the floor.
  • Possible to make a side or upper lighting window in the same series with the same look.
  • In the folding elements you can place another sash (e.g. top-hung window).

Performance level according to STS 52.0:

  • Air transmission: PA2
  • Mechanical resistance to wind: PV2
  • Watertightness: PE2

Performance level according to UEATC:

  • Air transmission: A2
  • Mechanical resistance to wind: V2
  • Watertightness: E2

Document Downloads

File Type Document Description Download Document
Adobe PDF Visofold Series
Product Data Sheet - IMS104DVS.201410
Download (3 MB)
Adobe PDF Technical Installation Guide
Bi-Fold Fitting Guide
Download (12.8 MB)
Adobe PDF Visofold Series
Supply only – Guide to installation
Download (403kb)

Technical Specification


Product Type Doors
Material Aluminium Polyamide
Dual Colour
Thermally broken
NBS available


Max width 6500
max height 2400
Max weight 80
Weather suitability ★★★★★
Acoustic suitability ★★★★
Thermal suitability ★★★★
Min Glazing 4
Max glazing 38
security rating ★★★★
low threshold option

Locking options




Building suitability

light duty
medium duty