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Aluminium Bifold Doors

Aluminium Bifold Doors Technical Details

Ultra Slim Sightlines

Smart LogoOur aluminium bifolding doors are constructed using Smart Systems VISOFOLD 1000 folding sliding door system. The door has been designed to eliminate the requirement for mullions between the panels and produces very slim sight lines of just 132mm. Doors are manufactured using Polyamide thermally broken aluminium profiles for superior insulation and durability and the system uses bespoke aluminium extrusions specifically designed for folding sliding doors to ensure effortless operation for years to come.

 Visofold technical banner

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. The Smart Systems Visofold 1000 Bi-fold door system uses dedicated aluminium profiles to produce a door that has simple clean lines and offers maximum visible glass areas.


Easy to Operate

Visofold 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.


Integrated Trickle Vents

Don't spoil the appearance of your new bifold door with ugly face fixed trickle vents.

Most bifold doors require trickle ventilation in order to comply with current building regulations but due to the slim design of the aluminium profiles the trickle vents have to be fitted to a frame extender fitted to the top of the door.  Face fixed external trickle vents spoil the aesthetics of any door so we now supply an exclusive and unique frame extender specifically designed to conceal trickle vents from view maintaining the slim lines of our aluminium folding sliding doors.  The design also provides a weather drip feature to the top of the doors enhancing the performance of the product.


concealed trickle ventilation exclusive frame extender
Concealed trickle ventilation Exclusive frame extender
Bottom Hinge Roller new enclosed rollers
New Fully Enclosed Rollers New Roller Underside View
traffic door handle internal handles
Traffic Door Handle* Internal Handles
magnet catch slim sight lines
Magnetic Retainer(Traffic door only) 132mm Sight Line


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


High Security Locking Standard

Our Visofold 1000 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.


Staycool Solar Control Glazing 1.0 U-value

staycool glassSTAYCOOL double glazing is now standard 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.

Alternatively, Planitherm Total + 1.2 U-value Low E argon filled double glazing can be substituted to allow solar gain at no extra cost.


Overall U-value

A Visofold 1000 door specified with our standard Staycool double glazing would typically acheive an overall 1.5 U-value and easily acheive Doc L 2010 building regulations compliance which require a 1.8 U-value of less.  Please note however that the actual overall U-value for a specific door will vary depending on the style and options chosen.  Further reductions in the U-value of our bifold doors is possible but would require the use of a different glazing specification such as Krypton gas and/or triple glazing at extra cost. If you have a specific requirement please contact us for a quotation.


Weather Rating

Visofold 1000 bi folding doors 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 132mm.  Where a traffic door meets folding sliding panels the sight line is 179mm and where two meeting stiles connect on 2/2(centrally split 4 panel)and 4/2(6 panel doors)the sight line is 226mm.


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 


Exclusive Frame Extender

frame extender open out door  frame extender open out doorOur unique 42mm high frame extender provides integral trickle ventilation for the door.


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



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