Why We Are In Love With Secondary Glazing Safety Features (And You Should Also!)

· 6 min read
Why We Are In Love With Secondary Glazing Safety Features (And You Should Also!)

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

Secondary glazing is frequently lauded for its exceptional thermal insulation and acoustic performance. However, beyond its capability to dampen the roar of city traffic or slash heating expenses, it works as a crucial security and safety layer for residential and industrial homes. For heritage buildings and sanctuary where replacing original windows is prohibited, secondary glazing provides a non-obtrusive method to bring high-level security to traditional structures.

This article explores the numerous safety features connected with secondary glazing, ranging 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, vulnerable panes discovered in historic single-glazed windows. When secondary glazing is set up, the option of glass is the primary determinant of how the unit will behave under effect.

Toughened Safety Glass

Toughened glass, also called 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 fragments, significantly lowering the danger of injury. This makes it an ideal choice for low-level windows or high-traffic areas where unexpected effect is a threat.

Laminated Security Glass

Laminated glass is the gold requirement for security. It consists of 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, keeping a barrier that is incredibly tough to penetrate. It is typically utilized in fashion jewelry shops and banks, making it a powerful deterrent against trespassers in a domestic setting.

Table 1: Comparison of Glass Types for Secondary Glazing

Glass TypeSecurity LevelSecurity CharacteristicFinest Use Case
Standard FloatLowGet into hazardous fragmentsNot advised for safety
StrengthenedMediumGet into little, blunt granulesHigh-traffic locations, doors
LaminatedHighFragments remain bonded to interlayerGround flooring windows, robbery prevention
Acoustic LaminatedHighSecurity plus sound reductionHigh-security city locations

Enhanced Locking Mechanisms and Hardware

A window is just as secure as its locking system. Secondary glazing adds a secondary physical barrier that a burglar should bypass. Since  secondary double glazing near halstead  is installed on the internal side of the primary window, it is protected from external tampering or using prying tools.

Multi-Point Locking Systems

For larger moving or sash units, multi-point locking systems can be utilized. These engage the frame at a number of points concurrently, making it practically difficult to jemmy the sash open. These systems are generally run by a single, ergonomic manage, making sure convenience does not come at the expenditure of security.

Secure Catches and Fasteners

Even for smaller units, such as horizontal sliders or lift-out panels, manufacturers use robust catches. Spring-loaded catches and fitch locks ensure that the panels are held securely within the frame, preventing them from being raised or moved by unapproved persons from the outside.

Key-Lockable Handles

Adding a key-locking feature to the secondary glazing supplies an extra layer of defense. In industrial environments or rental homes, this ensures that unauthorized individuals can not open the windows, which is especially useful for controlling ventilation or avoiding falls in high-rise buildings.


Fire Safety and Egress Considerations

While security is vital, the capability to exit a structure rapidly in the occasion of an emergency is similarly crucial. Secondary glazing must be developed to adhere to regional building regulations relating to fire egress.

Quick-Release Mechanisms

For windows designated as fire leaves, secondary glazing systems must be easily operable without the requirement for specialized tools or keys (unless those keys are kept in an understood, available area).

  • Egress Hinges: Casement secondary glazing can be fitted with 90-degree egress hinges, permitting the unit to widen enough for an individual to go through.
  • Easy-Slide Panels: Horizontal sliders are typically developed so that panels can be rapidly moved to one side or entirely raised out of the frame in an emergency.

Fire-Rated Secondary Glazing

In specific business or commercial applications, fire-rated glass may be required. This specific glass can hold up against extreme heat for a defined duration (e.g., 30 or 60 minutes), preventing the spread of flames and smoke through the building.


Child Safety and Fall Prevention

In multi-story structures, secondary glazing functions as a vital security barrier to prevent accidental falls, specifically involving kids.

Opening Restrictors

Opening restrictors are hardware components that restrict how far a window can be opened. Generally limited to about 100mm, these gadgets enable fresh air and ventilation while ensuring the gap is too small for a kid to crawl through. Many modern-day restrictors are "concealed," indicating they are built into the frame for a cleaner aesthetic, and can be disengaged by a grownup for cleaning or fire escape.

Safety Lists: Key Safety Features to Look For

When choosing a secondary glazing supplier, homeowner should guarantee the following safety features are discussed:

  • Standard Compliance: Does the glass fulfill BS EN 12150 (Toughened) or BS EN 14449 (Laminated) requirements?
  • Handle Ergonomics: Are the deals with simple to grip and run for those with limited mobility?
  • Interlock Gaskets: Do the sashes interlock when near to avoid the glass from being pressed through the frame?
  • Sub-Frame Strength: Is the wood or aluminum sub-frame firmly anchored to the main masonry to prevent the whole system from being forced out?

The "Double Barrier" Effect

Beyond individual functions, the large existence of secondary glazing supplies a mental and physical "Double Barrier." A trespasser taking a look at a house with single glazing sees a single, vulnerable pane of glass. If they see secondary glazing installed behind it, they realize they have 2 separate systems to penetrate.

The air space between the main and secondary window likewise acts as a buffer zone. In case of a heavy impact, the external window may break, but the secondary window-- frequently made from more powerful, laminated glass-- stays intact, avoiding entry and maintaining the structure's envelope.


Table 2: Safety Benefits Summary

FeatureMain Safety BenefitSecondary Safety Benefit
Laminated GlassBreak-in deterrenceUV protection (prevents fading)
Opening RestrictorsChild fall preventionManaged ventilation
Internal InstallationTamper-proof from the outsideSecurity from the components
Aluminum FramesStructural rigidityFire resistance (non-combustible)

Frequently Asked Questions (FAQ)

1. Does secondary glazing make it harder to get away in a fire?

If created correctly, no. Requirement installations for fire escape routes consist of "egress" windows or easy-to-operate sliders that meet structure security codes. It is vital to notify the installer if a window is a designated emergency situation exit.

2. Can secondary glazing be fitted with locks?

Yes. Many secondary glazing units come with numerous locking choices, including threaded bush locks, key-locking deals with, and security bolts to improve home security.

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

While older kids can operate deals with, the setup of opening restrictors can restrict the opening range to a safe width, preventing falls while still enabling air flow.

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

Secondary glazing is installed internally. This indicates a trespasser must first break through the main window and after that deal with a second, totally different locking system and glass barrier. Often, the noise and time needed to break through both are adequate to deter a criminal.

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

Not constantly by default, however reliable companies will use toughened or laminated glass as basic for larger systems or locations where safety is an issue. Constantly define that safety glass is needed when receiving a quote.


Secondary glazing is a multifaceted solution that provides much more than just a quieter, warmer home. Through the tactical use of laminated and toughened glass, robust internal locking hardware, and thoughtful egress style, it considerably upgrades the safety profile of any structure. For those residing in older residential or commercial properties or high-crime locations, 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 safety functions outlined above, property owners can guarantee their environment is not only comfy but likewise secure and certified with contemporary safety standards.