20 Things You Need To Know About Secondary Glazing Safety Features

· 6 min read
20 Things You Need To Know About Secondary Glazing Safety Features

Secure and Sound: An In-Depth Guide to Secondary Glazing Safety Features

Secondary glazing is often lauded for its exceptional thermal insulation and acoustic performance. However, beyond its capability to moisten the holler of city traffic or slash heating bills, it works as a vital security and security layer for domestic and industrial properties. For heritage buildings and sanctuary where changing initial windows is prohibited, secondary glazing uses a non-obtrusive way to bring top-level security to traditional structures.

This post explores the various safety features related to secondary glazing, varying from high-performance glass types to advanced locking mechanisms and fire egress considerations.


The Role of Glass in Safety and Security

The glass utilized in secondary glazing is significantly different from the thin, delicate panes discovered in historical single-glazed windows. When secondary glazing is installed, the choice of glass is the main factor of how the system will act under impact.

Toughened Safety Glass

Toughened glass, likewise referred to as tempered glass, is heat-treated to increase its strength compared to typical "float" glass. If it does break, it shatters into thousands of small, granular portions rather than sharp, rugged fragments, significantly minimizing the danger of injury. This makes it a perfect choice for low-level windows or high-traffic areas where unintentional impact is a danger.

Laminated Security Glass

Laminated glass is the gold standard for security. It includes two layers of glass with a polyvinyl butyral (PVB) interlayer sandwiched in between them. Even if the glass is struck with considerable force, the interlayer holds the pieces together, maintaining a barrier that is extremely difficult to penetrate. It is typically used in precious jewelry stores and banks, making it a formidable deterrent against burglars in a domestic setting.

Table 1: Comparison of Glass Types for Secondary Glazing

Glass TypeSecurity LevelSafety CharacteristicFinest Use Case
Basic FloatLowBreaks into dangerous fragmentsNot advised for security
StrengthenedMediumBurglarize little, blunt granulesHigh-traffic areas, doors
LaminatedHighPieces remain bonded to interlayerGround floor windows, break-in prevention
Acoustic LaminatedHighSafety plus noise decreaseHigh-security city areas

Improved Locking Mechanisms and Hardware

A window is only as safe and secure as its locking mechanism. Secondary glazing includes a secondary physical barrier that a trespasser need to bypass. Since the secondary unit is installed on the internal side of the main window, it is shielded from external tampering or the usage of spying tools.

Multi-Point Locking Systems

For bigger sliding or casement systems, multi-point locking systems can be utilized. These engage the frame at numerous points simultaneously, making it essentially impossible to jemmy the sash open. These systems are normally operated by a single, ergonomic deal with, ensuring benefit does not come at the expenditure of security.

Secure Catches and Fasteners

Even for smaller sized systems, such as horizontal sliders or lift-out panels, manufacturers make use of robust catches. Spring-loaded catches and fitch locks guarantee that the panels are held strongly within the frame, preventing them from being lifted or moved by unauthorized individuals from the exterior.

Key-Lockable Handles

Including a key-locking function to the secondary glazing provides an extra layer of defense. In business environments or rental residential or commercial properties, this ensures that unauthorized persons can not open the windows, which is especially beneficial for controlling ventilation or preventing falls in high-rise buildings.


Fire Safety and Egress Considerations

While security is crucial, the ability to exit a building quickly in the event of an emergency is similarly important. Secondary glazing should be created to adhere to local structure regulations concerning fire egress.

Quick-Release Mechanisms

For windows designated as fire gets away, secondary glazing systems must be easily operable without the need for specialized tools or secrets (unless those keys are kept in an understood, accessible location).

  • Egress Hinges: Casement secondary glazing can be fitted with 90-degree egress hinges, enabling the unit to open large enough for an individual to pass through.
  • Easy-Slide Panels: Horizontal sliders are typically created so that panels can be quickly moved to one side or completely raised out of the frame in an emergency.

Fire-Rated Secondary Glazing

In specific commercial or industrial applications, fire-rated glass might be needed. This customized glass can endure extreme heat for a defined duration (e.g., 30 or 60 minutes), preventing the spread of flames and smoke through the building.


Kid Safety and Fall Prevention

In multi-story buildings, secondary glazing acts as a crucial security barrier to avoid unintentional falls, particularly involving kids.

Opening Restrictors

Opening restrictors are hardware elements that restrict how far a window can be opened. Normally limited to about 100mm, these devices allow for fresh air and ventilation while making sure the space is too little for a kid to crawl through. Numerous modern restrictors are "concealed," meaning they are constructed into the frame for a cleaner visual, and can be disengaged by a grownup for cleansing or fire escape.

Security Lists: Key Safety Features to Look For

When choosing a secondary glazing service provider, homeowner should guarantee the following safety functions are talked about:

  • Standard Compliance: Does the glass satisfy BS EN 12150 (Toughened) or BS EN 14449 (Laminated) requirements?
  • Handle Ergonomics: Are the handles simple to grip and run for those with limited movement?
  • Interlock Gaskets: Do the sashes interlock when near to prevent the glass from being pressed through the frame?
  • Sub-Frame Strength: Is the lumber or aluminum sub-frame safely anchored to the main masonry to prevent the whole unit from being dislodged?

The "Double Barrier" Effect

Beyond individual functions, the sheer existence of secondary glazing supplies a mental and physical "Double Barrier." A trespasser looking at a home with single glazing sees a single, susceptible pane of glass. If they see secondary glazing installed behind it, they realize they have two separate systems to permeate.

The air gap in between the primary and secondary window likewise functions as a buffer zone. In case of a heavy impact, the external window might break, but the secondary window-- frequently made from stronger, laminated glass-- stays undamaged, preventing entry and maintaining the structure's envelope.


Table 2: Safety Benefits Summary

FeaturePrimary Safety BenefitSecondary Safety Benefit
Laminated GlassBreak-in deterrenceUV defense (avoids fading)
Opening RestrictorsKid fall avoidanceControlled ventilation
Internal InstallationTamper-proof from the outsideSecurity from the aspects
Aluminum FramesStructural rigidityFire resistance (non-combustible)

Frequently Asked Questions (FAQ)

1. Does secondary glazing make it more difficult to leave in a fire?

If designed properly, no. Standard setups for fire escape routes consist of "egress" windows or easy-to-operate sliders that meet structure safety codes. It is vital to notify the installer if a window is a designated emergency exit.

2. Can secondary glazing be fitted with locks?

Yes. The majority of secondary glazing units included different locking options, consisting of threaded bush locks, key-locking deals with, and security bolts to boost home security.

3. Is it possible for a child to open secondary glazing?

While older children can operate deals with, the setup of opening restrictors can limit the opening distance to a safe width, avoiding falls while still enabling airflow.

4. How does secondary glazing protect versus required entry compared to double glazing?

Secondary glazing is installed internally. This suggests a burglar must first break through the primary window and then handle a second, completely separate locking system and glass barrier. Frequently, the noise and time required to break through both are enough to hinder a criminal.

5. Is  secondary glazing installer in wickford  in secondary glazing always "security glass"?

Not constantly by default, however trusted business will use toughened or laminated glass as standard for larger systems or areas where security is a concern. Constantly specify that shatterproof glass is needed when receiving a quote.


Secondary glazing is a diverse solution that uses much more than just a quieter, warmer home. Through the tactical usage of laminated and toughened glass, robust internal locking hardware, and thoughtful egress design, it significantly upgrades the security profile of any structure. For those residing in older homes or high-crime areas, the addition of secondary glazing represents among the most efficient and least intrusive safety upgrades offered on the market today. By focusing on the specific security functions outlined above, homeowner can guarantee their environment is not only comfy but likewise protected and certified with contemporary safety requirements.