Why We Do We Love Secondary Glazing Safety Features (And You Should, Too!)

· 6 min read
Why We Do We Love Secondary Glazing Safety Features (And You Should, Too!)

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

Secondary glazing is often admired for its exceptional thermal insulation and acoustic performance. However, beyond  secondary glazing fitters stanford le hope  to dampen the roar of city traffic or slash heating costs, it functions as an important security and security layer for property and business homes. For heritage buildings and sanctuary where replacing initial windows is restricted, secondary glazing offers a non-obtrusive method to bring high-level security to standard structures.

This article checks out the numerous safety features associated with secondary glazing, ranging from high-performance glass types to sophisticated locking systems and fire escape factors to consider.


The Role of Glass in Safety and Security

The glass used in secondary glazing is significantly different from the thin, vulnerable panes discovered in historic single-glazed windows. When secondary glazing is set up, the choice of glass is the primary determinant of how the system will act under effect.

Toughened Safety Glass

Toughened glass, likewise understood as tempered glass, is heat-treated to increase its strength compared to regular "float" glass. If it does break, it shatters into countless small, granular chunks instead of sharp, jagged shards, substantially decreasing the threat of injury. This makes it an ideal choice for low-level windows or high-traffic locations where accidental impact is a danger.

Laminated Security Glass

Laminated glass is the gold standard for security. It consists of 2 layers of glass with a polyvinyl butyral (PVB) interlayer sandwiched between them. Even if the glass is struck with considerable force, the interlayer holds the pieces together, preserving a barrier that is extremely challenging to penetrate. It is often used in fashion jewelry stores and banks, making it a formidable deterrent versus intruders in a domestic setting.

Table 1: Comparison of Glass Types for Secondary Glazing

Glass TypeSecurity LevelSafety CharacteristicBest Use Case
Basic FloatLowBurglarize hazardous shardsNot suggested for security
StrengthenedMediumGet into little, blunt granulesHigh-traffic areas, doors
LaminatedHighPieces remain bonded to interlayerGround flooring windows, break-in avoidance
Acoustic LaminatedHighSafety plus sound decreaseHigh-security city locations

Improved Locking Mechanisms and Hardware

A window is just as safe as its locking system. Secondary glazing adds a secondary physical barrier that a trespasser need to bypass. Because the secondary system is set up on the internal side of the primary window, it is protected from external tampering or making use of prying tools.

Multi-Point Locking Systems

For larger moving or casement systems, multi-point locking systems can be utilized. These engage the frame at a number of points concurrently, making it essentially difficult to jemmy the sash open. These systems are normally operated by a single, ergonomic manage, making sure benefit does not come at the expense of security.

Secure Catches and Fasteners

Even for smaller sized units, such as horizontal sliders or lift-out panels, producers make use of robust catches. Spring-loaded catches and fitch locks ensure that the panels are held firmly within the frame, preventing them from being lifted or moved by unapproved individuals from the outside.

Key-Lockable Handles

Adding a key-locking function to the secondary glazing provides an extra layer of defense. In industrial environments or rental residential or commercial properties, this ensures that unauthorized persons can not open the windows, which is particularly helpful for controlling ventilation or preventing falls in skyscrapers.


Fire Safety and Egress Considerations

While security is vital, the capability to leave a building rapidly in the event of an emergency is similarly important. Secondary glazing should be developed to adhere to local structure guidelines regarding fire egress.

Quick-Release Mechanisms

For windows designated as fire gets away, secondary glazing units must be easily operable without the requirement for specialized tools or keys (unless those keys are kept in a known, available location).

  • Egress Hinges: Casement secondary glazing can be fitted with 90-degree egress hinges, enabling the unit to open large enough for a person to pass through.
  • Easy-Slide Panels: Horizontal sliders are often developed so that panels can be rapidly moved to one side or entirely lifted out of the frame in an emergency.

Fire-Rated Secondary Glazing

In particular business or industrial applications, fire-rated glass may be needed. This customized glass can hold up against extreme heat for a specified period (e.g., 30 or 60 minutes), avoiding the spread of flames and smoke through the building.


Child Safety and Fall Prevention

In multi-story buildings, secondary glazing functions as an important security barrier to prevent unintentional falls, particularly including kids.

Opening Restrictors

Opening restrictors are hardware components that limit how far a window can be opened. Generally limited to about 100mm, these devices enable for fresh air and ventilation while ensuring the gap is too small for a kid to crawl through. Lots of modern-day restrictors are "concealed," implying they are developed into the frame for a cleaner aesthetic, and can be disengaged by an adult for cleaning or emergency situation exit.

Security Lists: Key Safety Features to Look For

When selecting a secondary glazing service provider, residential or commercial property owners should make sure the following safety features are discussed:

  • Standard Compliance: Does the glass satisfy BS EN 12150 (Toughened) or BS EN 14449 (Laminated) requirements?
  • Deal with Ergonomics: Are the manages simple to grip and operate for those with restricted mobility?
  • Interlock Gaskets: Do the sashes interlock when near to prevent the glass from being pushed through the frame?
  • Sub-Frame Strength: Is the wood or aluminum sub-frame safely anchored to the primary masonry to avoid the whole system from being dislodged?

The "Double Barrier" Effect

Beyond specific features, the large existence of secondary glazing provides a mental and physical "Double Barrier." A trespasser taking a look at a house with single glazing sees a single, susceptible pane of glass. If they see secondary glazing installed behind it, they understand they have 2 different systems to permeate.

The air space in between the main and secondary window also serves as a buffer zone. In case of a heavy impact, the external window may break, however the secondary window-- typically made of more powerful, laminated glass-- stays undamaged, preventing entry and preserving the building's envelope.


Table 2: Safety Benefits Summary

FunctionMain Safety BenefitSecondary Safety Benefit
Laminated GlassTheft deterrenceUV security (prevents fading)
Opening RestrictorsChild fall avoidanceControlled ventilation
Internal InstallationTamper-proof from the outdoorsDefense from the elements
Aluminum FramesStructural rigidnessFire resistance (non-combustible)

Frequently Asked Questions (FAQ)

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

If designed properly, no. Requirement setups for fire escape routes consist of "egress" windows or easy-to-operate sliders that fulfill structure security codes. It is necessary to inform the installer if a window is a designated fire escape.

2. Can secondary glazing be fitted with locks?

Yes. Most secondary glazing systems included numerous locking choices, consisting of threaded bush locks, key-locking deals with, and security bolts to enhance home security.

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

While older children can operate handles, the installation of opening restrictors can restrict the opening distance to a safe width, avoiding falls while still permitting for airflow.

4. How does secondary glazing secure against forced entry compared to double glazing?

Secondary glazing is set up internally. This suggests an intruder needs to first break through the primary window and after that handle a 2nd, completely different locking system and glass barrier. Frequently, the sound and time required to break through both are sufficient to prevent a criminal.

5. Is the glass in secondary glazing always "shatterproof glass"?

Not constantly by default, but reputable business will utilize toughened or laminated glass as standard for larger units or areas where safety is a concern. Always define that security glass is required when getting a quote.


Secondary glazing is a multifaceted solution that provides much more than just a quieter, warmer home. Through the strategic usage of laminated and toughened glass, robust internal locking hardware, and thoughtful egress design, it significantly upgrades the security profile of any building. For those living in older residential or commercial properties or high-crime locations, the addition of secondary glazing represents one of the most efficient and least intrusive security upgrades readily available on the marketplace today. By concentrating on the particular security functions laid out above, property owners can guarantee their environment is not just comfortable but also safe and secure and compliant with modern security standards.