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Secondary Glazing - Hinged Units

Trusted - 10 Year Guarantee - Delivering Nationwide

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Aluminium Window & Door Manufacturers Since 1985

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

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Low Lying Flat Roof

High Security Locking • Slim Sightlines • Enhanced Thermal Performance

SYSTEM OPTIONS

Hinged Secondary Glazing Systems

A reduced range of hinged secondary glazing options grouped by operation type, with frame and fixing options shown clearly so it is easier to compare how each unit works and where it is best suited.

Butt Hinged Secondary Glazing
Wide Opening

Butt Hinged Units

A traditional hinged secondary glazing option designed to provide a large, clear opening. Ideal where easy access is needed and a slim, discreet frame is preferred.

Operation: Butt Hinge Opening: Approx. 150° Fixing: Face Fix / Reveal Fix Frames: Economy Odd Leg, Luxury Subframe
  • Can be hinged to one side or split in the middle as double butt hinged.
  • Secured shut with locking catches for added security.
  • Slim and unobtrusive sightlines make it well suited to heritage settings.
  • Suitable for single glazing up to 6.8mm.
Economy Odd Leg: Face fix only, fixed through an aluminium flange for quick, cost-effective installation.
Luxury Subframe: Face fix or reveal fix, with a timber subframe and trims for a cleaner, more finished appearance.
Friction Hinged Secondary Glazing
Controlled Ventilation

Friction Hinged Units

A hinged secondary glazing option that can be held open at intermediate positions, making it ideal where controlled ventilation and flexible opening are important.

Operation: Friction Hinge Opening: Approx. 65° Fixing: Face Fix / Reveal Fix Frames: Economy Odd Leg, Luxury Subframe
  • Can be held open at different angles between minimum and maximum opening.
  • Available as either top hung or side hung.
  • Secured shut with locking catches for added security.
  • Suitable for single glazing up to 6.8mm.
Economy Odd Leg: Face fix only, quick to install and the most affordable hinged system option.
Luxury Subframe: Face fix or reveal fix, with timber subframe, trims and a more traditional finished look.
GLASS OPTIONS

Secondary Glazing Glass Specification

A range of glass options designed to improve thermal performance, sound insulation, safety and privacy depending on your project requirements.

Glass Type Thickness Best For Key Benefits
Float Glass (Annealed) 4mm Standard use Good improvement in sound and thermal insulation
Obscure / Patterned Glass 4mm Privacy areas Maintains light while increasing privacy (bathrooms, bedrooms)
Toughened Glass 4mm Safety glazing Increased strength and security over standard float glass
Float Glass (Annealed) 6mm Larger panels Improved sound & thermal performance with greater strength
Toughened Glass 6mm Safety + larger sizes Stronger glass with added safety and security
Laminated Safety Glass 6.4mm Security & insulation High safety performance with improved sound and thermal insulation
Acoustic Glass 6.8mm Noise reduction Significant improvement in sound insulation
Double Glazed Unit 20mm Maximum performance Extreme thermal and acoustic performance (Heavy Duty system only)
COLOUR OPTIONS

Frame Finishes

Available in a selection of standard finishes, or any RAL colour to suit your project.

HIPCA White KL9910 Semi-Gloss
Van Dyke Brown BS08B29 Gloss
Silver Anodised Finish

Any RAL Colour

Choose from over 200 RAL colours for a fully bespoke finish. RAL finishes are special order and may extend lead times.

View RAL Chart
TECHNICAL DETAILS

Hinged Secondary Glazing Technical

Technical guidance for our hinged secondary glazing units, grouped by operation type and supported by key frame dimensions and sightline information for easier comparison.

1. Butt Hinged Units

Traditional hinged secondary glazing units designed for wide opening access, available as single or double butt hinged configurations.

Single Butt Hinge

Butt Hinge
Min. Width (mm)
300
Max. Width (mm)
900
Min. Height (mm)
400
Max. Height (mm)
2100

Double Butt Hinge

Butt Hinge
Min. Width (mm)
700
Max. Width (mm)
1800
Min. Height (mm)
400
Max. Height (mm)
2100

2. Medium Duty Butt Hinged Units

Panel-only hinged units intended for medium duty applications, available as either top hung or side hung.

Top Hung

Medium Duty
Min. Width (mm)
300
Max. Width (mm)
1250
Min. Height (mm)
400
Max. Height (mm)
1250

Side Hung

Medium Duty
Min. Width (mm)
300
Max. Width (mm)
1250
Min. Height (mm)
400
Max. Height (mm)
1250

3. Friction Hinged Units

Hinged units with friction stay operation for controlled opening, available in top hung and side hung formats.

Top Hung

Friction Hinge
Min. Width (mm)
350
Max. Width (mm)
1250
Min. Height (mm)
400
Max. Height (mm)
1000

Side Hung

Friction Hinge
Min. Width (mm)
300
Max. Width (mm)
650
Min. Height (mm)
400
Max. Height (mm)
1250

4. Key Dimensions & Sightlines

Shared frame dimensions and glazing information for the hinged secondary systems.

Economy Odd Leg

Frame Data
Outerframe Depth (mm)
25.5
Sash Depth (mm)
19.5
Glass (mm)
4 - 6.8
Max. Distance to Visible Glass (mm)
77
Vertical Interlock (mm)
77

Luxury Subframe

Frame Data
Outerframe Depth (mm)
37
Sash Depth (mm)
19.5
Glass (mm)
4 - 6.8
Max. Distance to Visible Glass (mm)
70
Vertical Interlock (mm)
77
Subframe Depths (mm)
SF1: 39 / SF3: 55 / SF4: 69
Important: Sizes shown are recommended only. Maximum widths can vary depending on height, and vice versa.
Special sizes: Requests under or over the recommended sizes may be possible, but the product may not carry a Duration guarantee.
Note: Vertical interlock applies to double butt hinged units only.
Luxury Subframe: Available with three subframe depths: SF1 39mm, SF3 55mm and SF4 69mm.
BROCHURES

Product Literature

Download specification sheets and full product brochures.

Secondary Glazing

Secondary Glazing Specification Guide

PDF • 5.5 MB Download
Secondary Glazing

Secondary Glazing Measuring Guide

PDF • 0.3 MB Download
Secondary Glazing

Secondary Glazing OCM

PDF • 0.3 MB Download
Secondary Glazing

Secondary Glazing Installation Guide

PDF • 2.0 MB Download
Secondary Glazing

Hinged Unit - Economy Odd Leg

PDF • 0.2 MB Download
Secondary Glazing

Hinged Unit - Luxury Subframe

PDF • 1.0 MB Download
Secondary Glazing

Hinged Unit - Medium Duty (FRAMELESS)

PDF • 0.2 MB Download
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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

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