Duration Windows - Aluminium Windows and Aluminium Doors Trade Manufacturer | Bi-folding Doors, Heritage Steel Replacement Windows, Secondary Glazing Supplier

Unbalanced Vertical Sliding Secondary Glazing

No Springs

Unbalanced Vertical Slider

A simple traditional vertical slider with unsupported sliding panels, often nicknamed the guillotine. A practical choice where a classic, discreet secondary glazing appearance is wanted.

Operation: Unbalanced Fixing: Face Fix / Reveal Fix Frames: Economy Odd Leg, Slim-line Equal Leg, Luxury Subframe

Panels are unsupported and secured open with a spring catch.
Panels can be removed for cleaning.
Slim and unobtrusive sightlines make it well suited to listed and heritage settings.
Suitable for single glazing up to 6.8mm.

Balanced Vertical Sliding Secondary Glazing

Spring Assisted

Balanced Vertical Slider

A more refined vertical slider with spiral or spring balances that hold the sash in position, making day-to-day use smoother and more convenient.

Operation: Balanced Fixing: Face Fix / Reveal Fix Frames: Economy Odd Leg, Slim-line Equal Leg, Luxury Subframe, Heavy Duty

Supported by balances so panels can stay in any open position.
Available in slim heritage-style frames or larger heavy duty options.
Can be single glazed up to 6.8mm, or double glazed in Heavy Duty format.
Well suited to both domestic and commercial applications.

Tilt Back Vertical Sliding Secondary Glazing

Balanced + Tilt Back

Balanced Tilt Back Vertical Slider

A balanced vertical slider with the added benefit of a tilt back facility, allowing the panels to tilt into the room for much easier internal cleaning.

Operation: Balanced Tilt Back Fixing: Face Fix / Reveal Fix Frames: Slim-line Equal Leg, Luxury Subframe

Panels are balance supported and can stay open at different positions.
Panels tilt back into the room for easier cleaning access.
Designed with slim, neat sightlines for a more discreet appearance.
Best suited to domestic use and single glazing up to 6.8mm.

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)

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)