What is Dynamic Glass, and How Does it Work
While the process for making flat, clear glass was perfected sometime after the Roman Empire, the functionality and application of windows have changed very little since the Middle Ages.
That is, until now.
What is Dynamic Glass
Dynamic glass, also called smart glass, electrochromic glass, switchable glass, or smart privacy glass, is a rapidly developing technology that is revolutionizing building construction and design. As the name suggests, dynamic glass changes its appearance in response to the environment and the user’s needs.
Dynamic glass can be altered, depending on the situation, making it appear transparent, translucent, or opaque. Certain types of dynamic glass also block ultraviolet (UV) and infrared (IR) light, which can significantly reduce energy bills.
How does Dynamic Glass Work
Dynamic glass comes in two main types: passive and active. The opacity of passive glass changes in response to temperature or light, while active glass requires an electrical charge, which can be applied on demand, to change its opacity.

Types of Passive Dynamic Glass
As its name suggests, passive glass does not respond to direct control. Instead, it responds to two external stimuli:
- Thermochromic glass uses heat from direct sunlight to change the tinting as needed. The more direct and intense the sunlight is on the glass, the darker it becomes.
- Photochromic glass changes its transparency in response to light intensity–the brighter the light, the darker it becomes. If you’ve ever seen transition lenses in sunglasses, you’ve seen this technology in use.
Types of Active Glass
Active glass is more complicated and comes in three types:
- Polymer Dispersed Liquid Crystal (PDLC)
- Suspended Particle Device (SPD)
- Electrochromic (EC).
I’ve included a brief description of each type of active glass below but have not included the technical details of how each works.
Features | Polymer Dispersed Liquid Crystal (PDLC) | Suspended Particle Device (SPD) | Electrochromic (EC) |
---|---|---|---|
Uses an electrical charge | X | X | X |
Can be dimmed | X | X | |
Blocks light | X | X | |
Blocks visibility | X |
Polymer Dispersed Liquid Crystal Glass
PDLC is opaque until an electrical charge is applied, at which point it becomes transparent. Dimming features allow varying degrees of transparency. This type of glass is best suited for interior use since it does not block light or provide shade.
The advantage of PDLC is that the objects behind the glass cannot be seen, making it perfect for privacy, projection, and whiteboard use. This product is ideal for conference rooms or private offices when used in office buildings since it provides privacy while allowing natural light to pass through.
Suspended Particle Device
Similar to PDLC, SPD is opaque until an electrical charge is applied. However, unlike PDLC, SPD does not turn completely opaque. Instead, it darkens to block up to 99% of incoming natural or artificial light within seconds of applying an electric current. SPD glass can be dimmed, allowing for custom shading.
Since SPD blocks sunlight, it is Ideal for exterior or sky-facing windows and has the added benefit of cooling interiors.
Electrochromic
Even though ECD uses an electric current like PDLC and SPD, the technology used to control opacity is very different. This difference means that the transition time is much slower and can take several minutes or more. However, once the transition from transparent to opaque is complete, no electric current or energy is required to maintain the current state.
ECD is ideal for exterior windows since it filters both light and solar heat. Like SPD, ECD is not suitable for providing privacy since it does not turn completely opaque.
The Benefits of Dynamic Glass
Dynamic glass has a variety of benefits, from reducing energy costs to providing privacy in public places. While it is most commonly used in schools, hospitals, and office buildings, dynamic glass can be used in most buildings and should not be overlooked for residential projects.
Dynamic glass used on exterior windows, whether passive or active, blocks up to 90% of solar heat. Considering about 76% of sunlight that falls on standard double-pane windows enters a building to become heat, dynamic glass can significantly lower cooling costs, conserve energy, increase comfort, and help your building become more energy efficient. It can even contribute credits toward LEED or BREEAM certification.
Dynamic glass also blocks up to 99% of all harmful UV light. Blocking UV light will protect the flooring, furnishings, and artwork from fading. The people living and working inside the building will also be protected from the potential damage UV light can cause to their skin and eyes.
By eliminating the need for window coverings, homes and offices can retain their views while blocking 90% of solar energy.
Privacy glass can be used in public and private spaces to obscure the view of people inside from those outside. Unlike glazing or frosting, which permanently obscure views, dynamic glass lets you retain beautiful views and control your need for privacy.
How to Install Dynamic Glass
Because passive glass does not require additional wiring, controls, sensors, or software, any glazier who works with standard insulating glass can install this type of window.
Active glass is more complicated and should only be installed by a professional company with relevant experience. Wires will need to be installed into the window frames, and the system will need to be wired into the existing electrical system.

Conclusion
While dynamic glass is a relatively new technology, its use and performance are rapidly improving. And, as the technology improves, the cost is declining. And, as temperatures increase around the globe, this technology will greatly help businesses and homeowners prepare.
The future of smart glass certainly looks bright.
FAQs about Dynamic Glass
Does it cost more than regular glass?
Yes, the initial cost will be higher than traditional windows. However, some of the costs can be recuperated over time through lower energy costs. Dynamic glass can also improve the experience and comfort of the occupants.
Are there less expensive solutions?
Yes, smart glass film is a less expensive alternative.
Does it come in different colors?
No, all the glass is clear. The different types of dynamic glass will appear more or less translucent depending on whether they are activated or not.
How do I control it?
For passive glass, no additional controls are required since the glass responds to changes in temperature and light. You can control active glass through a control panel mounted near the glass or wireless apps on a phone, tablet, or other device.
What are the consequences of a power outage?
If there is a power outage, the glass will transition to its default state as described above.
Can it only be installed in new buildings?
No, existing windows can be retrofitted with any of the solutions described above.