Most secure windows (PAS 24)

Windows are a common entry point for opportunist break-ins, so it pays to treat security as a baseline requirement rather than an optional extra. The good news: there's a recognised UK standard that does the hard testing for you.

What PAS 24 means

PAS 24 is the UK's enhanced-security standard for windows and doors. To pass, a window is subjected to a series of mechanical and manual attack tests that simulate the tools and techniques a burglar might use — prising, cutting, drilling and manipulating the hardware. A window that carries genuine PAS 24 certification has demonstrably resisted those attacks. It's also a requirement for new-build homes under Building Regulations, which tells you it's a meaningful bar, not marketing.

What makes a window hard to force

• Multi-point locking. Instead of a single catch, the sash locks to the frame at several points, spreading the load and resisting levering.
• Laminated or toughened glass. Laminated glass holds together when struck, so it can't simply be smashed for entry.
• Robust hinges and keeps. Anti-lift and reinforced hinge protection stops the sash being jemmied out.
• A strong, well-reinforced frame. A weak frame undermines even the best lock — see best upvc windows on why reinforcement matters.

How to check a window really meets it

Anyone can say “secure”, so verify it. Ask the installer to confirm the exact window is tested to PAS 24 and to put it on the quote. Look for third-party certification (such as a recognised product-certification scheme) rather than a self-declared claim, and confirm the glass specification and locking as separate line items. A reputable company will happily provide the paperwork — a reluctance to do so is itself telling. Our guide on choosing a double glazing company covers the wider checks.

The fit matters as much as the frame

A PAS 24 window installed badly — poorly packed, out of square or with the locking points not engaging fully — loses much of its protection. That's why accreditation and workmanship count. For exposed or high-risk locations you may also want to think about weather resistance alongside security; the rules for conservation areas can also affect what you're allowed to fit. If your current windows are structurally sound, it's still worth asking repair or replace first? — upgraded locks and laminated glass can sometimes be retrofitted.

Funding and contribution options may be available, subject to eligibility and a home survey, to help with a security-focused upgrade.