What is PAS 24 security glazing?

PAS 24:2022 is the UK standard for enhanced security performance of windows and doors. It tests complete window assemblies against physical attack. Most new-build properties in England require PAS 24 windows under Approved Document Q. The test involves sustained manual attack on the frame, hardware and glazing.

What is the difference between BS EN 356 ratings?

BS EN 356 rates glazing from P1A to P8B. P1A-P5A test resistance to a dropped steel ball at increasing heights. P6B-P8B test resistance to axe attacks with increasing strike counts. For domestic security, P1A or P2A is usually sufficient. P6B and above suit commercial and high-security applications.

Is laminated glass more secure than toughened glass?

Yes. Laminated glass has a PVB interlayer that holds fragments together when broken, making it very difficult to penetrate. Toughened glass is stronger but shatters into small pieces allowing easy entry. For security, laminated or laminated-toughened combinations are always specified.

Do I need PAS 24 windows by law?

Under Approved Document Q, all new-build homes in England must have windows and doors meeting PAS 24 or equivalent. This applies to conversions creating new dwellings too. Replacement windows in existing homes do not legally require PAS 24 but it is strongly recommended by police and insurers.

How much do security windows cost compared to standard?

PAS 24 windows typically cost 15-30% more than standard. Higher BS EN 356 ratings (P2A and above) can cost 50-200% more. The main cost difference is the laminated glass and upgraded hardware. Frame costs are similar as most modern frames already meet PAS 24 with multi-point locking.

TradeCalculator.co.uk

Window Security Calculator

Calculate security glazing specifications and costs for PAS 24 and BS EN 356 rated windows. Compare security levels and estimate upgrade costs for UK properties.

Security LevelPAS 24 required for new builds

Frame TypeAll with multi-point locking

Glazing UnitDouble or triple glazed

Number of Windows

Total windows to upgrade

Window Width

Individual window width

Window Height

Individual window height

How We Calculate This

This calculator estimates security glazing specifications and costs based on security rating, window size and frame type.

The formula

Total Cost = (Glass Area × Security Glass Rate × Unit Multiplier) + (Perimeter × Frame Rate × Qty) + (Install × Qty)

Glass cost varies by BS EN 356 / PAS 24 security rating
Triple glazed units add ~35% to glass cost
Frame cost per linear metre by material type
Installation cost per window for fitting and hardware

UK standards

PAS 24:2022 — Enhanced security for windows/doors
BS EN 356 — Security glazing P1A-P8B
Approved Document Q — Security in dwellings

Frequently Asked Questions

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Last updated: March 2026

All calculations are estimates. Verify with your supplier.