Bifold Windows WeatherTight™

Bifolds are a popular and versatile window, with a wide opening to maximise views and airflow. Bifolds play a wonderful role in connecting the inside to the outside.

Bifolds are available as standard or in a Inline version, which folds back flush with the exterior cladding.

WT Bifold window

Bifold Window Configurations

Colonial Glazing Bars     Passive Ventilation     Hardware     Jamb Liners     Flashings


Maximum sizes for bifold windows vary by width, height, wind zone, and glazing requirement. Your local Bradnam's branch will be able to advise you whether a configuration is possible or contact Altus Technical support.

As a guide, bi-fold window panels up to 1.4m high by 0.8m wide are recommended.

Frame Types

  • Open in and open out frames with a 19mm facing cover and 24mm glazing pocket (available only as screwed frame). Available in top hung or bottom rolling.
  • Inline fold back bi-fold open out option, which incorporates a smooth sill, is available.
  • An over light transom and heavy duty adaptor are available.

Glazing, Beads and Panel Types

  • Hinges at panel junction. The surface fitted hinges at these junctions achieve 2 critical objectives:
              – unbroken seals between the door stiles
              – an uncluttered appearance when doors in the open position with no visible hinge plates or screws.
  • Beaded rails and stiles can be used to provide for a wide range of glazing options from 4mm to 24mm.
  • A range of 11 beads are available to accommodate glazing options from 4mm to 24mm and to provide a variety of finishing styles from sloped to square.
  • A French door adaptor and sash adaptor are also available within the range.


  • For bifold windows, we recommend fully captive configurations 2 and 0, 2 and 2, or 4 and 0.
  • We do not recommended loose panel options with an odd number of panels sliding in one direction, i.e. 2 and 1, 3 and 0, 4 and 1, or 3 and 2. This is because the configuration requires additional latching, which may be difficult to operate in some instances such as over a kitchen bench.


Window Ventilation

Aluvent passive ventilator enables passive ventilation to be included into all bi-fold window panels. Refer to the Aluvent section.



A standard range of flashings include 95mm, 84mm,71mm, 68mm, 63mm, 58mm, 53mm, 48mm, 45mm, 41mm, 38mm, 31mm, 25mm and 14mm. These have been designed to comply with E2/AS1 Amendment 6 requirements. Refer to the flashings section.



Proprietary Altus NZ Limited bifold hinge and bifold roller assemblies are critical components to provide attractive visual and functional performance of doors and windows. Refer to the hardware section.