Laminated vs Toughened Glass for Security: The Complete Guide

In this article, you’ll discover:

• The fundamental difference between laminated and toughened glass
• Why toughened glass offers zero security benefit
• How BS EN 356 security ratings work
• Real cost comparisons for upgrading your glazing

There’s a common misconception: “toughened glass is security glass.” We hear it all the time from homeowners. And it’s completely wrong.

Both glass types are stronger than standard float glass. But they behave completely differently when someone tries to break through. One provides genuine security. The other keeps your family safe from accidents but won’t slow down a burglar.

This guide explains what each type does, how security ratings work, and when you should invest in upgraded glazing for your timber windows.

Toughened Glass: Safety, Not Security

Toughened glass — also called tempered glass — is heat-treated to be 4-5 times stronger than standard glass. The manufacturing process creates surface tension that makes it significantly harder to break.

Here’s the thing: when toughened glass does break, it shatters completely into small, relatively harmless granules. That’s the point — it’s designed as safety glazing, protecting people from dangerous shards. But that same property makes it useless for security — once broken, there’s no barrier left.

Where Toughened Glass Should Be Used

Building Regulations (Approved Document K) require safety glass in ‘critical locations’:

• Glazing within 800mm of finish floor level
• Glazing in doors and side panels within 300mm of doors
• Low-level glazing in bathrooms

Toughened glass is also more resistant to thermal stress — useful where glass experiences temperature differences.

Laminated Glass: The Real Security Option

Laminated glass consists of two or more glass panes bonded with an interlayer — typically PVB (polyvinyl butyral) or EVA resin. This interlayer is the key to everything.

When struck, the outer glass may crack or shatter, but the pieces stay bonded to the interlayer. The glass doesn’t fall away. To get through, an intruder must keep hitting the same spot repeatedly, gradually breaking through layer after layer.

This delay defeats most break-in attempts. Burglars typically want to be in and out within 2-3 minutes. Spending 30-60 seconds hammering at a window that won’t give way — making noise the whole time — isn’t worth the risk.

Additional Benefits

• Superior sound insulation — the interlayer dampens vibrations
• UV protection — blocks up to 99% of UV rays
• Safety compliance — also qualifies as safety glass under Building Regulations

BS EN 356 Security Ratings Explained

BS EN 356 is the European standard for testing glass resistance to manual attack. The standard divides into two categories:

Ball drop tests (P1A to P5A): A steel ball dropped from increasing heights. Measures resistance to opportunistic attack.

Axe tests (P6B to P8B): Glass struck repeatedly with an axe. Measures resistance to sustained attack.

Class	Test Method	Typical Application
P1A	3 ball drops from 1.5m	Basic residential
P2A	3 ball drops from 3m	Standard residential upgrade
P4A	3 ball drops from 9m	High-value homes
P6B-P8B	30-70+ axe blows	Commercial, high-risk

For most residential applications, P2A or P4A provides excellent security. Higher ‘B’ ratings are designed for banks and commercial premises.

Cost Comparison

Realistic figures for 2026 (per m² of glass):

• Toughened: +£15-25 over standard float glass
• Laminated (basic): +£35-45
• Laminated (P2A): +£45-55
• Laminated (P4A): +£55-70

For a typical sash window (1.2m²), P2A laminated adds £55-65. For 10-12 windows? Around £500-800 extra. Some insurers offer premium discounts for certified security glazing.

Making the Right Choice

Choose toughened when:

• Building Regulations require safety glass
• The window is prone to accidental impact
• Thermal stress is a concern

Choose laminated when:

• Security is a genuine concern (ground floor, rear of property)
• You want improved sound insulation or UV protection
• Insurance requires or incentivises security glazing

Best of both worlds: Many timber window manufacturers supply double-glazed units with toughened inside and laminated outside — Building Regs compliance plus genuine security.

Frequently Asked Questions

Is laminated glass burglar proof?

No glass is truly burglar-proof, but laminated glass significantly delays break-in attempts. Even basic laminated can withstand several minutes of sustained attack. The delay usually deters opportunistic burglars.

Is toughened glass the same as safety glass?

Toughened is one type of safety glass. Laminated also qualifies under BS 6206 and EN 12600. Both reduce injury risk — toughened by shattering into granules, laminated by holding fragments together.

Which is better for noise reduction?

Laminated provides significantly better acoustic insulation. The PVB interlayer dampens sound vibrations, reducing noise by 3-5 decibels more than standard double glazing.

Do I need security glass on all windows?

Focus on vulnerable points: ground-floor windows, accessible rear windows, glazed doors, and windows hidden from view. Upper floors visible from the street are lower priority.

The Bottom Line

If security is your goal, laminated glass is the only sensible choice. Toughened is excellent for safety but won’t delay a break-in. The upgrade cost isn’t as high as many assume — for ground-floor windows, it’s an investment that makes real sense.

At Timber Windows Direct, we supply windows with any glazing specification. Contact us to discuss the right options for your property.