A shop’s front window is not just its most visible feature. It is also one of the main sources of heat loss in the premises. Choosing the right type of glass affects both the security of the store and its heating and cooling costs throughout the year.
There are three main types of glass used in shopfronts: toughened glass, laminated glass and secondary glazing. Each one addresses a different need: impact resistance, anti-theft security or energy savings. Many shopfronts combine several of these solutions within the same glazing unit, which is exactly what we handle as part of our commercial glazing service.
Types of glass for commercial shopfronts
Toughened glass
Toughened glass undergoes a heat treatment that increases its resistance to knocks and impacts. If it breaks, it shatters into small, less sharp fragments, reducing the risk of serious injury. It is a common choice for shopfronts in high-footfall areas.
Laminated glass
Laminated glass is made up of two or more layers of glass bonded together with an interlayer (typically PVB). When it breaks, the fragments stay attached to that inner layer and the glass remains held together within its frame. This makes it particularly well suited to deterring attempted break-ins or vandalism, as it stays in place even after impact.
Secondary glazing
Secondary glazing combines two panes of glass separated by an air gap or inert gas (such as argon). This gap acts as an insulator and reduces heat transfer between the inside and outside of the premises. It is the go-to solution when the main priority is cutting the shopfront’s energy consumption.
| Type of glass | Impact resistance | Breakage behaviour | Provides thermal insulation | Main use in retail |
|---|---|---|---|---|
| Toughened glass | High | Small, less sharp fragments | Not significantly | Protection against accidental impacts |
| Laminated glass | Medium to high | Stays intact after breaking | Not significantly | Anti-theft and anti-vandal protection |
| Secondary glazing | Depends on the inner pane used | Depends on the inner pane used | Yes, notably | Energy savings and thermal comfort |
Toughened vs laminated glass: what’s the difference?
The main difference between toughened and laminated glass lies in how they behave when broken. Toughened glass shatters into small, separate fragments. Laminated glass stays together thanks to its inner interlayer, even after impact.
For shopfronts with high-value stock on display or a history of attempted break-ins, laminated glass is usually the more suitable choice, as it maintains a physical barrier even once the glass has broken. For areas at risk of accidental knocks without that anti-theft requirement, toughened glass is a more cost-effective alternative.
What is low-E glass and why does it matter for a shopfront?
Low-E glass (low-emissivity glass) is a type of glass coated with a very thin layer of metallic oxides that reflects part of the thermal radiation. This coating lets visible light through while reducing heat loss in winter and heat gain in summer.
In a commercial shopfront, this effect has a direct impact on the energy bill. A premises with its shopfront lit and heated or cooled for 10 to 12 hours a day turns any thermal leak into a daily cost. Replacing standard glass with low-E glass, usually fitted as part of a secondary glazing unit, reduces that leak and eases the load on the heating and cooling system.
This solution does not change the appearance of the shopfront or reduce the amount of natural light inside. Its effect is purely thermal, so it does not compromise the visibility of the products on display.
These kinds of glazing upgrades also feed into the premises’ overall energy rating. If you’d like to understand how that consumption is assessed and what documentation is required, take a look at our guide to the energy certificate for retail shops in Spain.
How to choose the right glass for your shopfront
The right choice of glass depends on three factors: how exposed the location is, the main priority (security or energy savings), and whether it’s a single shop or a network of several stores.
- Premises in high-footfall areas or with a history of breakages: laminated glass or toughened safety glass.
- Premises with intensive heating or cooling, or high energy bills: secondary glazing with low-E glass.
- Retail chains and franchises with several locations: it is worth standardising the glazing criteria across the whole network, so every store maintains the same level of security and energy efficiency regardless of location.
In many cases, the most effective solution combines several of these properties within the same glazing unit: for example, secondary glazing with laminated safety glass on the outer pane and low-E glass on the inner pane. Standardising these decisions across the network is also one of the most effective ways to reduce maintenance costs in the long run.
Frequently asked questions
Is low-E glass more expensive than standard glass?
Yes, it has a higher upfront cost than standard glass. That extra cost is offset over time through lower heating and cooling consumption, especially in premises where the shopfront is in use for many hours a day.
Can low-E glass be fitted to an existing shopfront?
It depends on the current structure of the shopfront. In most cases it requires replacing the entire glazing unit with a double-pane unit that includes the low-E coating, as this treatment is applied during the manufacture of the glass itself.
Does safety glass (toughened or laminated) also help with thermal insulation?
Not significantly on its own. Thermal insulation depends mainly on the air gap within secondary glazing and the low-E coating, rather than on the type of safety treatment applied to the glass.
Is a specific type of glass mandatory for a commercial shopfront?
Regulations do not require a specific type of glass in every case, but they do set safety requirements depending on the location and risk profile of the premises. It’s worth reviewing each case with a specialist to ensure guaranteed regulatory compliance for the glazing installed.
