Your car’s side windows are made of safety glass, but not all safety glass is the same. Most vehicles use either laminated or tempered (also called toughened) glass for the side windows. While both types are designed with safety in mind, they behave differently in crashes, daily comfort, and even noise reduction.
In this article, we’ll explore what those differences actually mean for everyday UK drivers — from how each type affects safety, comfort, and UV protection, to how they perform in break-ins, how much they cost, and whether there are any legal or insurance implications.
What’s the Difference?
Laminated glass is made of two or more layers of glass bonded together with a plastic film (usually PVB). When it breaks, the pieces stick to the plastic layer instead of falling away. This is the same kind of glass that’s used in all windscreens.
Tempered glass, on the other hand, is a single pane that’s been heat-treated to make it stronger. When it breaks, it shatters into many small, blunt pieces that are less likely to cause injury.
Tempered side windows are still the standard in most vehicles, but laminated glass is becoming more common — especially in newer or higher-spec models.
Safety Considerations
When it comes to safety, both types have their strengths.
Laminated windows tend to stay in one piece when broken, which helps prevent people or objects from being thrown out of the car in a collision. They can also provide better protection against objects coming into the vehicle.
Tempered windows shatter completely when struck, which can make it easier to escape the vehicle in an emergency. For example, tools designed to break windows work well on tempered glass — but often struggle with laminated panes. This is something to bear in mind when choosing a car or buying an escape tool.
So it’s a trade-off: laminated glass offers better protection in some crash scenarios, while tempered glass allows for quicker exit in emergencies.
Noise and UV Protection
Laminated glass has extra benefits beyond crash safety. The plastic interlayer acts as a sound barrier, reducing wind and road noise inside the cabin. It also blocks a large amount of ultraviolet (UV) rays — up to 95% in many cases — which can help protect your skin and prevent your car’s interior from fading.
Tempered glass doesn’t offer the same level of sound or UV protection, though some tempered windows may be tinted or treated to reduce glare.
Break-in Resistance
Laminated side windows are significantly more resistant to break-ins. Because the glass sticks together even when shattered, it’s much harder for a thief to smash through quickly.
Tempered glass, by contrast, will shatter immediately with a sharp blow. That’s great for emergencies, but unfortunately it also makes smash-and-grab thefts easier.
Some car security ratings even award higher marks to vehicles with laminated side glazing, precisely because of this added protection.
Cost and Availability
Tempered glass is cheaper to manufacture and easier to replace, which is why it’s still used in the vast majority of vehicles. If you have a broken side window on a car with tempered glass, it’s typically a quicker and less expensive fix.
Laminated glass is more complex and usually more expensive to repair or replace. It’s often found in newer or higher-end cars as a premium feature. If you wanted to retrofit laminated glass into a car that didn’t originally have it, that could involve modifications to the window frame — and a much higher cost.
UK Laws and MOT Rules
In the UK, both laminated and tempered glass are legal for side windows, as long as they meet safety standards. There’s no specific law requiring side windows to be laminated.
The main legal requirement is about light transmission. Front side windows must let in at least 70% of visible light. If your windows are too dark (especially after adding tints), you could face fines or even an MOT failure.
In terms of safety, your windows must be marked with the appropriate certification — such as a British Standard or E-mark — to prove they’re made from approved safety glass. Both laminated and tempered types can meet this standard.
Insurance and Repairs
From an insurance point of view, most comprehensive car insurance policies in the UK include cover for glass — whether it’s your windscreen or side windows.
The type of glass in your vehicle usually doesn’t affect your premium, though some insurers may charge more for replacement parts if your car has laminated side windows. That said, if you make a claim for a broken window, it’s typically treated as a separate glass claim. You’ll usually just pay the glass excess, and it won’t affect your no-claims bonus.
Some UK providers also offer standalone windscreen and glass cover if you’re not on a comprehensive policy.
If your car does have laminated side glass, it’s worth checking your insurer’s terms to make sure the cover includes those more expensive replacements.
Final Thoughts
Whether your side windows are laminated or tempered, both types meet safety standards and do their job well. Tempered windows are the standard for most cars and are great for affordability and ease of escape. Laminated windows offer a more premium feel, added security, and better noise and UV protection — but they cost more to repair.
For everyday UK drivers, there’s no need to worry if your car has one type or the other, but it’s helpful to understand the differences. If you’re choosing a new vehicle, this is one more feature to consider — especially if comfort, security, or long-term interior protection is a priority.
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