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Aluminium Bifold Doors

Technical Details

Ultra Slim Sightlines

Cortizo logo   Smart Logo

We offer a choice of Smart Systems Visofold 1000 Slim aluminium bifolding doors with a 122mm wide sightline or you can take the upgrade to the new Cortizo Bifold-Plus door which has 110mm wide sightlines and also provides an overall 0.8 u-value with optional triple glazing.

 Bifold-Plus sightlines

Why choose aluminium bifold doors?

Aluminium folding sliding doors are strong and durable with slim sightlines and can be specified to open in or out. Whichever bifold door system you choose your door will be manufactured using dedicated aluminium profiles to produce a door that has simple clean lines and maximises the visible glass area.


Easy to Operate

Our bi-folding doors slide effortlessly using bottom fitted dual rollers running on a dual track and also have the benefit of nylon guide rollers at the top which ensures positive and easy movement of the individual door panels during the fold and slide operation.  The doors have internal fold flat handles and D handles to intermediate panels together with lever/lever handles to traffic doors.  A magnet retaining catch is supplied with doors that provide a traffic door to prevent the hinged door leaf self closing.


traffic door handle internal handles
Traffic Door Handle* Internal Handles
magnet catch slim sight lines
Magnetic Retainer(Traffic door only) 122mm Sight Line


*Traffic door handle style may vary if RAL colour handle option is required


High Security Locking Standard

Visofold 1000 and Cortizo Bifold-Plus folding doors are fitted with high security mulit-point locking system on all traffic doors to ensure your peace of mind. For doors without a traffic door operation of the shoot-bolt locking system is only accessible from the inside using the key operated lockable meeting stile twist handles. Doors with a traffic door will have a lever handle operated multi-point hook lock system fitted similar to a normal entrance door. The handle also includes a profile key cylinder deadlock facility which is accessible from both inside and outside enabling a conventional entrance door facility without opening up the complete door.


Solar Control Glazing 1.0 U-value

staycool glassSTAYCOOL double glazing is available as an upgrade on all our aluminium folding sliding doors offering an exceptionally low 1.0 U-value ensuring maximum heat is retained in the colder months of the year. The solar control benefits of STAYCOOL also provide shelter from direct sunlight in the summer by reflecting 57% of direct heat from the sun and reduce glare by 35%. STAYCOOL is a neutral solar control glass and does not have a coloured tint.


Overall U-value


When specified with standard argon filled low e double glazing or the solar control upgrade the door will acheive an overall 1.5 u-value and easily achieve current building regulations compliance with a Window Energy Rating band C.  



This bifold door offers a combined 1.4 u-value using standard double glazing or 0.8 u-value when taking the triple glazing option and fully complies with current building regulations.

Please note however that the actual overall U-value for a specific door may vary depending on the configuration and options chosen.  


Weather Rating

Both systems have been tested to BS 6375: Part 1: 2009 meeting all the requirements for air permeability, watertightness and resistance to wind loads.  A copy of the test report is available on request.


Visofold 1000 Bifold Door Glass Sight lines

For panels moving in the same direction the sight line is 122mm.  Where a traffic door meets folding sliding panels the sight line is 169mm and where two meeting stiles connect on 2/2(centrally split 4 panel)and 4/2(6 panel doors)the sight line is 206mm.


Visofold 1000 - Technical Data

Minimum Door Width (incl outerframe)


Maximum Door Width (incl outerframe)


Minimum sash width


Maximum sash width


Maximum sash weight


Maximum Door Height



*Doors are available wider than 6 metres on request.
**Maximum height dependant on installation location.

Download Profile Sight Lines And Technical Details For Visofold 1000 Bifold Doors


Outer Frame Head

frame head


Weathered Threshold

weathered thresholdRecommended for external applications and usually fitted onto a projecting cill. The weathered threshold provides a rebate for the doors to seal against ensuring full protection from the elements.  It is often possible for the threshold to lowered in the external brickwork to create a flush level on the inside.


Low Threshold

low thresholdDesigned for internal applications the 15mm non-weathered low threshold can be sunk into the floor if required or used in conjunction with optional wheelchair ramps.


Outer Frame Jamb

frame jamb


Hinged Meeting Stiles

meeting stile


Lock Meeting Stile

lock meeting stile


Projecting Cill Options

cill options150mm or 190mm cills are available 


View the most common questions asked about our bifolds on our FAQ page



View Visofold Brochure



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