Security for Windows – Everything You Need to Know

Security for Windows – Everything You Need to Know

When it comes to securing a building, windows can present the greatest challenge. Whereas doors are likely to be limited in number and located conspicuously, windows are often numerous and sometimes located away from the public eye.

Considerations when tackling this challenge include the location of the building, the location of the windows, the size of the windows, the aesthetics of the building and the overall cost.

Here at APE Fire and Security, your building security is our priority, so we thought we’d share some different ways you can secure windows. If you’d like to learn more about our security services, simply get in touch with us today.

Glazing for Security

There are a number of types of glass and glazing materials used in windows and some types provide more security than others.

Perhaps the first and most obvious piece of advice is to replace any broken panes of glass or broken double glazed sealed units, especially if they are located in accessible windows. Beyond that the choice of glazing will depend on your budget and the level of vulnerability of a window.

Different Types of Window Glass


Sheet glass is cheap and can often be found in greenhouses and sheds.  It provides no security other than the noise it makes when it is broken and the fact that it can cause injury.


Float or plate glass is used as glazing for windows.  As with sheet glass, it provides no security other than noise and the potential for injury when broken.


Wired glass is usually made from float glass and is often seen in fire doors.  The wires help to hold the glass together in fires. This glass in its basic form provides no security value and is less likely to make noise and cause injury than float glass.

Toughened/ Tempered

Toughened or Tempered glass is a form of specially treated float glass used as a safety glass in commercial premises.


Laminated glass consists of two pieces of glass sandwiching a plastic interlayer. In the event of the glass breaking the interlayer holds the whole structure in place preventing a hole in the window through which an intruder could gain access to the building. When broken, it also free from shards that could cause injury. Laminated glass can be found in both car windscreens and shop fronts.

Toughened Laminated Glass

Toughened Laminated Glass can offer the benefits of both toughened and laminated glass, being strong and yet staying in place when broken.

Alternatives to Security Glass


A popular alternative to glass for windows is Plexiglass, a composite product consisting of acrylic and petroleum-based substances, often referred to as acrylic glass.

Plexiglas has an impact resistant several times stronger than untoughened glass and is shatter resistant, making it a great deterrent to intruders. They would need to exert far more pressure on plexiglass to make a crack in it than glass and when Plexiglass is combined with security glass film, it is virtually impossible to undermine its security.


Polycarbonate is a plastic which is stronger than Plexiglas and is hard to crack, break or chip and therefore deterring any potential intruder. Polycarbonate comes in different grades and a key consideration when choosing polycarbonate is the end use. Polycarbonate sheets can also come with a hard coating which gives it a harder finish and improves its scratch resistance, nullifying another potential problem.

Security Glazing Film

An economical security solution is to apply security film to your windows, creating an unbreakable barrier invisible to the eye and yet impenetrable.

Window security film is easy to install and is low maintenance. The film provides privacy by using one-way mirroring, which prevents intruders from viewing the inside of your offices.

Window security films come in a variety of thicknesses and can be applied onto windows but needs to be positioned behind the glazing beads or bars in order to be fully effective and therefore should be professionally installed.  The film operates rather like the PVB interlayer in laminated glass in that it holds the glass together when it’s broken.


Aside from the type of glazing used, locks can enhance your window security. The choice of aftermarket window lock will depend on the type of window you have.

  • Pin locks – are ideal for installing on ground floor windows as they can prevent intruders from lifting windows.
  • Keyed locks – require keys to get them open, although locating the keys can be an issue.
  • Hinged wedge locks – prevent double-hung windows, one that can open from both top and bottom, from being opened. They can be adjusted in order that you can open the window partially if installed higher on the frame of the window.
  • Sash locks – allow a window to open, but also hold it shut in place. These locks are typically found on double-hung windows.

Grilles, Bars and Shutters

A more radical way to provide window security is to install a security grille. There are several different types of grilles which come with different levels of security, aesthetic appeal and price.

Security Mesh

The window mesh is both simple and cost effective in providing security from intruders. It is generally welded into a frame and can be fitted either flat to a wall or alternatively stood off the wall using legs, to allow windows to be opened. There can also be cut outs made into the grille to allow for such considerations as handles, pipes and vents, or indeed any other obstruction.

Fixed Window Bars

Fixed window bars provide a high level of window security. They can be fitted either internally or externally and provides a strong and durable deterrent to any potential intruder.

Windows can still be opened when window bars are fitted internally, which allows ventilation without compromising security. When fitted externally, the bars reduce the risk of window breakage. They come in a variety of designs, some quite decorative.

Removable Window Bars

This type of window bar is ideal for commercial applications where the removal of the security bars is occasionally required, and the window opening falls below the minimum size required for retractable window grilles. The window bars are locked into place on the inside of windows but can be easily released from the inside from a single radial lock point to allow easy access for maintenance and visibility.

Tube and Link Security Shutters.

The tube and link style security shutters are mainly used in shops such as jewellers and normally fitted inside the windows. They are employed on medium security commercial sites where see-through vision is important as they offer high visibility and can be used internally behind glass for shop displays.

Window Sensors

An alternative to providing physical barriers as a window security measure is to install window sensors. These devices are designed to detect whenever a window is opened, and in the case of some security systems, will chime an alert to let you know whenever this has happened.

Get Started with APE Fire and Security

If you’d like to learn more about our building security solutions here at APE Fire and Security, simply get in touch with our expert team today. We can provide tailored advice for your windows and other areas of your building to best suit your requirements.

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