The most important thing to know about window security ratings in the UK is that PAS 24 is the baseline test for modern windows, not a premium upgrade.
If you are buying new or replacement windows, you might assume that a security rating is an optional extra. That is not the case. Since 2010, Approved Document Q of the Building Regulations for England and Wales has required that all new windows and replacement windows meet a minimum security standard (GOV.UK, 2026).
PAS 24 is the mandatory minimum security rating for new and replacement windows in England and Wales under Building Regulations. Secured by Design (SBD) offers a higher police-preferred standard. Check your window's certification before installing.
- PAS 24 is the mandatory minimum for new and replacement windows in England and Wales since 2010.
- The PAS 24 test simulates a forced entry attempt lasting 3 to 5 minutes.
- Secured by Design (SBD) goes beyond PAS 24 with laminated glass and tougher hardware.
- BS 7950 is an older standard, now largely replaced by PAS 24 in Building Regulations.
- Scotland requires equivalent security under Section 6 of its Building Standards.
- The most important thing to know about window security ratings in the UK is that PAS 24 is the baseline test for modern windows, not a premium upgrade.
- How PAS 24, SBD, and BS 7950 compare as security ratings
- Quick numbers — key security ratings side by side
- The direct answer to "What is the best window security rating for my home?"
- How to verify a window's security rating — installer and product certification
- What the security rating does NOT cover — glass type, hinge strength, and installation quality
The standard is PAS 24, which stands for Products and Systems for Enhanced Security. It is the British Standard test that simulates a forced entry attempt by a human attacker. The main test lasts 3 minutes, and an enhanced version lasts 5 minutes. During this time, the attacker uses common tools such as screwdrivers, crowbars and hammers to try to open the window. A window that passes PAS 24 is not unbreakable. It is designed to resist a casual, opportunistic attack. If a window does not carry PAS 24 certification, it cannot legally be installed in a new-build or replacement scenario in England and Wales as of the 2026 Building Regulations update. Scotland has its own equivalent under Section 6 of the Building Standards.
How PAS 24, SBD, and BS 7950 compare as security ratings
Three main security ratings exist for windows in the UK. PAS 24 is the mandatory minimum for new and replacement windows under Building Regulations. It is a whole-window system test, not just a lock or glass test. The entire window unit, including the frame, glass, hinges and locks, is tested together as one system (BRE, 2026).
Secured by Design (SBD) is a police-preferred standard that goes beyond PAS 24. SBD windows must first pass PAS 24 and then meet additional criteria. These typically include laminated glass of at least 6.8mm thickness and specific hinge and lock configurations. SBD products are listed on the official SBD register run by Police Crime Prevention Initiatives (Secured by Design, 2026).
BS 7950 is an older British Standard for enhanced security windows. It is less common in 2026 because PAS 24 has largely replaced it. Some existing stock or retrofit windows may still reference BS 7950. It tests the window as a whole, like PAS 24, but with slightly different test durations and force levels.
Quick numbers — key security ratings side by side
| Rating name | Governing body | Test focus | Typical glass requirement | Typical lock requirement | Typical cost uplift vs unrated window |
|---|---|---|---|---|---|
| PAS 24 (minimum for new/replacement) | BSI / British Standards | Whole window system | Not specified (test uses standard glass) | Multi-point locking system | No additional cost (it is the baseline) |
| SBD (police-preferred) | Police Crime Prevention Initiatives | Whole window system plus additional criteria | Laminated glass (usually 6.8mm) | Specific hinge/lock configurations | Approximately 10–15% more than a PAS 24 window |
| BS 7950 (older standard, less common) | BSI | Whole window system | Not specified | Multi-point locking system | Variable, often no longer available new |
| No certification (only existing/retrofit) | N/A | N/A | Standard float glass | Single or basic lock | £0 (no upgrade cost, but no tested security) |
Cost uplift figures are based on industry estimates from the Glass and Glazing Federation (GGF, 2026).
The direct answer to “What is the best window security rating for my home?”
For a new-build or full replacement, PAS 24 is the legal minimum. You cannot legally choose less. The best is SBD if you want the highest tested resistance. SBD windows are tested to a higher standard and are recommended by police forces across the UK (Secured by Design, 2026).
For a retrofit or secondary glazing, PAS 24 is not required legally. But if you are upgrading, look for a window that carries PAS 24 certification. If the window frame cannot be replaced, the best practical option is a window lock that meets TS 007 (a lock-only standard) with a Kitemark (BSI Kitemark, 2026). TS 007 tests the lock itself, not the whole window system.
For existing windows without certification, the best security upgrade is a lock that meets TS 007 and a hinge-side restrictor. These do not change the window’s overall rating but improve resistance to forced entry.
Approved Document Q (GOV.UK, 2026) confirms that PAS 24 is the baseline for new and replacement windows in England and Wales.
How to verify a window’s security rating — installer and product certification
To verify a window’s security rating, check the product’s data sheet or the manufacturer’s website for a specific PAS 24, SBD, or BS 7950 test report number. The report must come from a UKAS-accredited test laboratory (UKAS, 2026).
For SBD, check the official SBD product register online (Police Crime Prevention Initiatives). SBD certification is product-specific, not installer-specific. A window model either has SBD approval or it does not.
For installation quality, the installer must be registered with a competent person scheme for windows. In England and Wales, this is typically FENSA or CERTASS (FENSA, 2026). This is a legal requirement for replacement windows. FENSA registration does not guarantee security, but it confirms the installer is legally allowed to self-certify compliance with Building Regulations, including security requirements.
For locks alone, look for a Kitemark or TS 007 mark on the lock itself. The lock should be a 5-lever mortice lock for timber frames or a multi-point locking system for uPVC frames (BSI Kitemark, 2026).
What the security rating does NOT cover — glass type, hinge strength, and installation quality
PAS 24 and SBD test the whole window system, but they do not explicitly rate the glass’s resistance to impact from a brick or other heavy object. For that, look for a glass standard like BS EN 356, which classifies glass as P1A, P2A, P3A, etc. (BRE, 2026). Laminated glass is common in SBD windows but is not mandated by PAS 24.
Hinge strength is tested as part of the system, but a poorly installed hinge can bypass the rating. For example, if screws are too short and do not bite into the frame properly, the hinge may fail even if the window model passed its test. Installation quality is not tested by PAS 24.
The rating only applies to the window as tested. If you change the lock, glass, or hinge, the rating is void unless the replacement parts are identical and tested as part of the same system (Secured by Design, 2026).
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Frequently Asked Questions
PAS 24 is the British Standard test for window security, mandatory for new and replacement windows under Building Regulations in England and Wales since 2010. It tests the whole window unit against a 3-minute forced entry attempt using common tools, as defined by BRE.
Yes, Secured by Design (SBD) is a higher standard than PAS 24, requiring laminated glass and specific hardware. SBD windows must first pass PAS 24, then meet additional police-preferred criteria set by Secured by Design.
PAS 24 is a whole-window system test, while BS 7950 is an older standard focusing only on locks and hardware. PAS 24 has largely replaced BS 7950 in UK Building Regulations since 2010, according to GOV.UK.
Yes, replacement windows in England and Wales must meet PAS 24 under Approved Document Q of Building Regulations as of 2026. Scotland requires equivalent security under Section 6 of its Building Standards.
The PAS 24 test uses common tools such as screwdrivers, crowbars and hammers to simulate a casual, opportunistic attack. The test lasts 3 minutes for the standard version and 5 minutes for the enhanced version, as specified by BRE.
