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Manufactured in the UK with Nationwide Support

Trusted - 10 Year Guarantee - Delivering Nationwide

Aluminium Window & Door Manufacturers Since 1985

UK Made • 10-Year Warranty • Nationwide Delivery • FastTrack Available

Modern Aluminium Window & Doors

High Security Locking • Slim Sightlines • Enhanced Thermal Performance

Standard White & Conventional Colour Range

Standard White

Standard White

9910 Gloss
Graphite Black

Graphite Black

9005 Matt

This comprehensive range of conventional colours are available at a reduced cost and a reduced lead time, when compared to special RAL colours.

Anthracite Grey

Anthracite Grey

7016 Matt
Dove Grey

Dove Grey

7035 Semi Gloss
Ivory Cream

Ivory Cream

1015 Semi-Gloss
Brown

Brown

8017 Matt

Textured / Structural Metallic Colours

Textured Dark Grey

Textured Dark Grey

9008 Structural Metallic

If you're looking for something a bit different then our structural metallic textured paint finish is for you. It's not a tacky finish but has a completely different and contemporary look and feel, when compared to most conventional colour finishes.

Your doors will stand out as a defining feature of your home when painted in our Grey 9008 Structural Metallic Paint Finish.

Please note that these on-screen representations of painted colours are for guidance only, intended to provide an indication of colour.

Duration Windows cannot be held responsible for any discrepancies between on-screen and actual painted colours.

RAL Colour Finishes

Grey

Grey

9007 Semi-Gloss
Blue

Blue

5011 Matt
Red

Red

3004 Matt

Our Bi-folding Doors are available in any single or dual special RAL colour paint finish. There are over two hundred different RAL colours available.

Click the link below to see a selection of the available RAL colours.

See Our RAL Colour Chart

GLASS OPTIONS

Examples of Popular Glass Options

Choose from clear, laminated, solar control and integral blind options to suit performance, privacy and comfort requirements.

i
Frames and doors are supplied unglazed for safer transport and easier handling on site.
Supplied unglazed glass option
Supplied Un-glazed
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A simple and popular everyday glazing choice offering strength and clarity.
Standard clear toughened glass
Standard Clear Toughened
i
Added security and safety performance with laminated inner construction.
Laminated security glass
Laminated Security Glass
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Low-emissivity clear glass designed to improve thermal efficiency.
Pilkington Activ Clear glass
Pilkingtons Activ™ Clear
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Neutral appearance glazing helping reduce solar gain while maintaining light transmission.
Pilkington Activ Neutral glass
Pilkingtons Activ™ Neutral
i
Solar control glass with a more neutral finish for improved comfort in brighter elevations.
Sun-guard Super Neutral glass
Sun-guard Super Neutral
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High performance thermal glass option developed for improved insulation.
SGG Planitherm One glass
SGG Planitherm ONE
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Integral manual blinds fitted within the sealed unit for privacy and reduced maintenance.
Push block manual blinds glass option
Push Block Manual Blinds
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Electrically operated integral blinds contained within the glazing unit for convenient light control.
Electronic control unit blinds glass option
Electronic Control Unit Blinds

Please note: Glass is supplied separate of the frames and the doors will need to be glazed on site. This helps improve transport and handling while helping ensure your doors arrive in excellent condition.

HARDWARE OPTIONS

Premium HI Bifold Hardware

Premium bifold hardware engineered for strength, smooth operation and a clean, contemporary aesthetic.

Traffic Door Handle

Traffic Door Handles

With a conventional and ergonomic design, lever-lever handles are an industry standard. Lever-lever handles are fitted to the internal and external of each traffic door, allowing inside and outside access.

They can also be fitted to the inside only, upon request, depending on the required configuration and access arrangement.

Finishes: White, Black, Chrome, Silver or any RAL colour finish.

Intermediate Pop-out T-Handles

Intermediate Pop-out T-Handles

Designed in collaboration with Duration’s technical designers, these slim-line, aesthetically pleasing pop-out T-handles are fitted to each intermediate panel.

They drive shoot bolt locking and are fitted to the inside of the door only, so they cannot be operated from the outside.

Finishes: White, Black, Chrome, Silver or any RAL colour finish.

Four Wheel Bogie Assemblies

Four Wheel Bogie Assemblies

These high quality, high strength bogie wheel assemblies run on twin stainless steel tracks and have been tested to take over 200kg in weight — more than three times the weight of the doors.

This provides a smooth, easy-glide opening action for years to come, with dedicated bogie guides for added stability and security.

Finishes: White, Black or any RAL colour finish.

High Strength Traffic Door Buffer Magnets

High Strength Traffic Door Buffer Magnets

High strength buffer magnets are used to help retain and control the traffic door in the open position where required.

They are a neat and practical addition that helps manage the movement of the door set during day-to-day operation.

Finishes: White, Black or Dark Grey.

What Is a Traffic Door?

A traffic door allows quick and easy access from the inside and outside of your bifolding doors, without having to slide and fold any panels — just as you would with a conventional back door.

If your chosen style does not allow for a traffic door, you will have no outside access and at least two panels must be folded to open the doors.

Bi-folding doors slide in two’s, so an uneven number of folding panels will result in an odd panel that can operate independently. This odd panel is known as a traffic door.

Find Out More
SECURITY FEATURES

Built For Security Without Compromise

Premium HI bifold doors have been designed and manufactured with security in mind, combining robust hardware, secure glazing and dependable locking points to help keep your home safe and secure every day.

Six key security features working together

When anyone has new windows or doors installed in their home, security is always at the forefront of their mind. That is why all of our doors have been designed and manufactured with security in mind, delivering excellent security without compromise.

From high security multi-point locking and superior cylinders through to internally glazed units and anti-jemmy bogie guidance, every detail has been developed to help keep the system safe, secure and dependable.

  • High security multi-point locking
  • Superior locking cylinder
  • Lockable pop-out T-handles
  • Heavy duty shoot bolts
  • Dedicated bogie guide
  • High security glazing
Premium bifold door security diagram
Threshold Options

Premium HI Bifold Thresholds

Choose from fully weather rated standard rebated thresholds, lower flush threshold options for low to medium exposed locations, ramped low thresholds, or room divider thresholds for internal use only.

54mm Standard Rebated Threshold (CA)

A fully weather rated threshold option available for both open in and open out door configurations, with or without a cill.

Open out standard threshold

Open Out Standard Threshold

Fully weather rated. Reference: CA-01.

Open in standard threshold

Open In Standard Threshold

Fully weather rated. Reference: CA-06.

Open out standard threshold and cill

Open Out Standard Threshold & Cill

Fully weather rated. Reference: CA-03.

Open in standard threshold and cill

Open In Standard Threshold & Cill

Fully weather rated. Reference: CA-08.

34mm Flush Low Threshold (CB)

A lower flush threshold option recommended for use in low to medium exposed areas, available for open in and open out doors, with or without a cill.

Open out low threshold

Open Out Low Threshold

Recommended for use in low to medium exposed areas. Reference: CB-01.

Open in low threshold

Open In Low Threshold

Recommended for use in low to medium exposed areas. Reference: CB-06.

Open out low threshold and cill

Open Out Low Threshold & Cill

Recommended for use in low to medium exposed areas. Reference: CB-03.

Open in low threshold and cill

Open In Low Threshold & Cill

Recommended for use in low to medium exposed areas. Reference: CB-08.

34mm Ramped Flush Low Threshold (CC)

A lower ramped threshold option recommended for use in low to medium exposed areas, designed to provide a more gradual transition at floor level.

Open out ramped low threshold

Open Out Ramped Low Threshold

Recommended for use in low to medium exposed areas. Reference: CC-01.

Open in ramped low threshold

Open In Ramped Low Threshold

Recommended for use in low to medium exposed areas. Reference: CC-02.

22mm Flush Low Non-Thermal Threshold (CD)

A room divider threshold option for internal use only, where weather performance is not required.

Open out room divider threshold

Open Out Room Divider Threshold

For internal use only. Reference: CD-01.

Open in room divider threshold

Open In Room Divider Threshold

For internal use only. Reference: CD-02.

Flush low threshold options are recommended for use in low to medium exposed areas, while the room divider threshold is for internal use only. Standard rebated threshold options are fully weather rated.
The images shown are an artistic representation only and are not intended as a comprehensive installation guide. Please also note that only the bi-folding doors are supplied. Associated items such as decking, flooring and lead flashing are not supplied as part of the bifold door system.
Technical Details

Premium HI Bifold Technical

Technical information and specification guidance for the Premium HI bifold door system, including sizes, sight lines, performance and opening styles.

Recommended Sizes

Min. Width (mm)
1400
Max. Width (mm)
6250+
Min. Height (mm)
1000
Max. Height (mm)
2750
Max. Panel Width (mm)
1200
Max. Weight (kg)
100

Widths over 6250 can be achieved but may require a mechanical join. Heights of up to 3000mm can be achieved subject to panel width and location. Panels can also be made less than 700mm wide — please contact our technical department for advice.

Key Profile Dimensions

Outerframe Depth (mm)
70
Sash Depth (mm)
70
Glazed Sealed Units (mm)
24, 28, 32
Projection Cill Height - Optional (mm)
25
Head Extension - Optional (mm)
20, 40
Transom / Mullion - if Required (mm)
32

Door Panel Size Guide

No. of Door Panels 2 3 4 5 6 7 8+
Min Width (mm) 1400 2100 2800 3500 4200 4900 Please Ask
Max Width (mm) 2400 3600 4800 6000 7200 8400 Ask

Please remember all sizes are for guidance only and are subject to location of the fitted product. Please contact us for more information.

*Please be advised: doors over 2500mm tall may be subject to a wind loading check. In that case, we will need to know the location, postcode and facing of the doors.

Bifolding Door Performance

DOC L Complies with regulations
600 Pa Air permeability
600 Pa Water tightness
2400 Pa Wind resistance

These statistics apply for open out doors with a suitable glass unit, achieving air permeability Class 4, water tightness meeting and exceeding requirements for Class 9A, and wind resistance meeting Class AE2400. Weather tested in accordance with BS6375 Part 1 & 2.

Specifying - Suitable Applications

  • Can be specified for residential / domestic applications.
  • Meets building regulations for new build. (For June 2022)
  • Meets building regulations for replacement and refurbishment projects. (For June 2022)
  • Standard fully weather rated threshold; suitable for use up to second floor and exposed locations.
  • Flush low threshold options; suitable for use on the ground floor only, not recommended for use in exposed locations or properties situated by the coast.

Sight Lines

Head / Top (mm)
110
Jamb / Side (mm)
110
Meeting Stiles (mm)
140
Bottom - Std. Rebated Threshold (mm)
130
Bottom - Low Flush Thresholds (mm)
130
Bottom - Room Divider Threshold (mm)
118

The details for the bottom sight-lines and step height are the optimum / best case scenario for open out doors that have been sunk / dropped into the floor.

Opening Styles

Doors shown are all viewed from the outside. All doors can be made to open in or out and there is no cost implication to choosing open in or open out doors.

Available opening styles for up to a 7 panel bifold
BROCHURES

Product Literature

Download specification sheets and full product brochures.

Premium HI Section Identification

Premium HI Section Identification

PDF • 3.6 MB Download
Premium HI Assembly Guide

Premium HI Assembly Guide

PDF • 0.5 MB Download
Premium HI Threshold Details

Premium HI Threshold Details

PDF • 0.5 MB Download
Premium HI

Premium HI Floating Corner Post

PDF • 0.8 MB Download
Premium HI

Premium HI Bifold

PDF • 7.5 MB Download
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Made in UK
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Proprietors: Quailfalcon Limited. Registered in England and Wales under company number 1913793. VAT registration number GB545958986. Reg. Office: Thames Development, Charfleets Road, Canvey Island, Essex SS8 0PQ. Company Director: G. Chelton

We reserve the right to change specifications. Terms & Conditions. We continuously wish to improve and we kindly inform you that all incoming and outgoing phone calls may be recorded for quality and training purposes.

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