Window security ratings for UK homes

Burglary remains one of the most disruptive crimes a household can experience, and windows represent the most common point of entry in domestic break-ins across England and Wales. Yet when most homeowners replace their windows, security performance rarely features in the conversation. Price, colour, and energy efficiency tend to dominate, while the question of how well a window actually resists a determined attack gets overlooked entirely. That is a significant blind spot, because the difference between a window that passes independent security testing and one that does not can be the difference between a burglar walking away frustrated and one walking through your living room. Understanding window security ratings in the UK gives you the knowledge to ask the right questions, compare products fairly, and make a purchase that genuinely protects your home rather than just looking as though it does.

Why Window Security Ratings Matter More Than Most Homeowners Realise

According to the Office for National Statistics Crime Survey for England and Wales, windows and doors account for the majority of successful forced entries in domestic burglaries. Many of those entries do not involve sophisticated tools or prolonged effort, opportunistic burglars typically look for the path of least resistance, and a window that can be levered open in under a minute is exactly that.

The assumption that any double-glazed window offers meaningful security protection is understandable but mistaken. A uPVC double-glazed window can look perfectly solid while offering almost no resistance to a crowbar at the frame, a screwdriver at the glazing bead, or a sharp blow to the handle. The security performance of a window depends on its design, materials, hardware, and glazing, and those factors vary enormously between products that may appear almost identical from the street.

In 2026, two standards are the most relevant reference points for UK homeowners shopping for replacement windows. The first is PAS 24, a British Standards Institution specification that defines enhanced security performance requirements and requires independent verification. The second is Secured by Design, the official UK police initiative that licences products meeting or exceeding PAS 24 and adds further criteria in some product categories. Knowing what these standards mean, and what they do not cover, puts you in a much stronger position when speaking to window installers.

Practical tip, when a salesperson describes a window as “secure” or “reinforced,” ask them to name the specific standard it has been tested to and whether they can provide written evidence. A genuine answer will reference PAS 24 or Secured by Design by name.

What PAS 24 Actually Means in Plain English

PAS stands for Publicly Available Specification, and PAS 24 is published by the British Standards Institution. It sets out enhanced security performance requirements for windows and doors used in domestic buildings. The current version is PAS 24:2022, which is the edition you will see referenced on compliant products available in 2026.

What does testing actually involve? A manufacturer submits a window specimen, a complete unit including frame, glazing, locks, handles, and hinges, to a UKAS-accredited testing laboratory. Technicians then attempt to force entry through the window using a defined set of tools and methods that reflect the tools a realistic opportunistic burglar might carry. The tests include attempts to lever the frame, drill through the lock mechanism, force the hinges, attack the glazing bead, and break through the glass unit itself. Each test must be completed within a set time period, and the window must resist without allowing passage or allowing the locking mechanism to be defeated.

A critical point worth emphasising is that PAS 24 compliance cannot be self-declared by the manufacturer. The testing must be carried out by a laboratory holding UKAS accreditation, which means an independent body has assessed the laboratory’s competence and impartiality. When you see PAS 24 referenced on a product specification sheet, the accreditation behind it carries genuine weight, it is not a marketing badge a company can apply to itself.

PAS 24 covers the complete window system, not individual components. A frame that is strong on its own but fitted with a weak handle does not pass. A solid lock fitted into a frame without adequate steel reinforcement does not pass. This systems approach is what makes PAS 24 a meaningful standard rather than a partial reassurance.

Practical tip, ask your window supplier to show you the actual PAS 24 test certificate for the specific product range being quoted, not just a reference to the standard in their brochure. The certificate will name the test house and the product model.

Secured by Design and What the Police-Preferred Logo Tells You

Secured by Design is the official UK police security initiative, operated under the authority of the National Police Chiefs’ Council. It licences physical security products, including windows, doors, and glazing, that meet independently verified performance standards. The familiar blue and white SbD logo on a window is a signal that the product has been assessed against at least PAS 24 as a baseline requirement and that the manufacturer holds a current licence.

One feature of Secured by Design that distinguishes it from simply passing PAS 24 is the ongoing nature of the licensing obligation. Manufacturers do not pass a single test and then display the logo indefinitely. They must maintain compliance with assessment criteria and are subject to review. This means that when you see the SbD logo in 2026, it reflects a current relationship between the manufacturer and the scheme, not a one-off result from several years ago.

In some product categories, Secured by Design goes beyond PAS 24 by specifying additional features. For windows, this can include requirements for multi-point locking as standard, laminated glazing as a minimum glass specification, and internally fitted glazing beads. These requirements reflect known vulnerabilities that testing has identified as real-world attack routes.

Homeowners can use the Secured by Design product database at the official SbD website to check whether a specific window model from a specific manufacturer currently holds a licence. This takes a matter of minutes and is something you can do before signing any contract. If a salesperson tells you their windows are Secured by Design but the product does not appear in the database, that is a significant concern worth investigating before proceeding.

guide to choosing a window installer in the UK

Practical tip, before your installation appointment, search the Secured by Design product database using the manufacturer name and product range. Print the result or save a screenshot to confirm the licence is current.

How Window Security Ratings Compare at a Glance

There are several standards and schemes that may come up when you are researching or purchasing replacement windows. Understanding how they relate to each other helps you interpret what a salesperson or brochure is telling you and spot whether any gaps exist in the product being proposed.

Part Q of the Building Regulations, which applies to new builds and certain extensions in England, mandates PAS 24 compliance as a legal requirement. This means buyers of new-build homes constructed after Part Q came into force should already have windows meeting the standard, though it is still worth requesting confirmation from the developer. Homeowners in older properties replacing windows voluntarily are not legally required to meet PAS 24, but police forces and the Association of British Insurers strongly recommend it.

The BSI Kitemark for security is worth a brief explanation because it sometimes creates confusion. The Kitemark is a BSI scheme that certifies products are being manufactured consistently to a tested standard, it is a manufacturing quality mark as much as a security performance mark. When you see a Kitemark on a security-rated window, it adds confidence that the product coming off the production line matches the specimen that passed the test. Some products carry Secured by Design certification, some carry the Kitemark, and some carry both. Neither is invalid, both are credible forms of independent verification.

Practical tip, if a quotation document references BS 7950 as the security standard, ask the installer whether the product also meets PAS 24:2022, since BS 7950 is an older specification that has been largely superseded in current practice.

Which Window Frame Material Performs Best for Security

A common question homeowners ask is whether uPVC, aluminium, or timber windows are more secure. The honest answer is that all three materials can achieve PAS 24 compliance when properly engineered, but they behave very differently under physical attack, and the risks associated with a poorly specified product vary by material.

uPVC is by far the most common window frame material in UK homes. On its own, uPVC can flex under force, which means that without internal reinforcement, typically a steel or aluminium insert running through the profile, the frame may be used apart without the locks being defeated at all. A PAS 24-compliant uPVC window will have this reinforcement as a standard design feature, but a cheaper uPVC window that has not been tested to the standard may lack it. This is one of the clearest reasons why the PAS 24 label on a uPVC product actually means something.

Aluminium frames are inherently stiffer and denser, which gives them a natural advantage in resisting the kinds of levering and forcing attacks that PAS 24 tests simulate. However, aluminium window security still depends heavily on the quality of the locking hardware and the design of the glazing bead. A stiff frame with inadequate locks does not pass testing, and aluminium is not immune to attack at those points.

Timber frames have been used in UK homes for centuries and can absolutely achieve modern security ratings when fitted with appropriate hardware. The key consideration with timber is age, if you have original or older timber windows that predate the introduction of modern security standards, they are unlikely to offer comparable resistance, and the hardware fitted at the time of installation may have been designed purely for operation rather than forced-entry resistance.

uPVC versus aluminium windows, which is right for your home

Practical tip, regardless of frame material, ask specifically what steel or aluminium reinforcement is used inside the profile and request confirmation that the specific product (not just the material type) has been tested to PAS 24 as a complete system.

The Role of Glass in Window Security Ratings

Many homeowners focus on the frame and locks when thinking about window security, but the glass unit itself is a critical component, and often the weakest link in a window that has not been specified with security in mind. Standard float glass, the type used in basic glazing units, offers very little resistance to deliberate attack. A sharp blow with a hard object will break it quickly, and once broken it can be cleared from the frame to allow entry in a matter of seconds.

Security-rated windows address this through laminated glass. Laminated glass consists of two or more panes bonded together with a plastic interlayer, typically polyvinyl butyral (PVB). When laminated glass breaks, the interlayer holds the fragments together rather than allowing the pane to shatter outward. This means that a burglar who breaks laminated glass is left with a fractured but largely intact sheet that is difficult and time-consuming to remove, rather than a clear opening. The noise and time required to deal with laminated glass is a significant deterrent.

PAS 24 testing includes specific assessments of the glazing bead, the strip of material that holds the glass unit within the frame. In older double-glazed windows, external glazing beads (fitted on the outside face of the window) were common, and they could be removed with a flat blade. This allows the entire glass unit to be pushed inward from outside without the locks being touched at all. PAS 24-compliant windows use internally fitted beads, meaning the bead can only be removed from inside the property. This is a straightforward design change but an important one.

When reviewing quotes for replacement windows, ask two specific questions about the glazing. First, is the glass in the unit laminated, and if so, in which pane, the inner pane, the outer pane, or both? Second, are the glazing beads fitted internally? These questions will quickly reveal whether the installer is working to a security-conscious specification.

double glazing explained, what is inside your window unit

Practical tip, for ground-floor windows and any window accessible from a flat roof or outbuilding, specify laminated glass as a minimum on both panes of the double-glazed unit, not just the inner pane.

Locking Systems and Hardware That Make a Real Difference

The lock and handle system fitted to a window can make or break its security performance, quite literally. Multi-point locking systems, in which the window engages at several points along the frame simultaneously rather than at a single central point, are a standard feature of any PAS 24-compliant window. The logic is straightforward, a single locking point creates a lever pivot around which the frame can be forced open, whereas multiple locking points along the height of the window distribute that resistance and make forcing dramatically harder.

Within multi-point systems, homeowners will encounter various types of hardware described by terms such as shootbolts, espagnolette bolts, and hook bolts. You do not need to memorise these terms to make a good purchasing decision, but you should ask any installer to confirm that the window locks at multiple points along the frame when the handle is engaged, and ideally ask them to demonstrate this on a sample or show you a diagram of where the locking points are positioned.

Handles are worth specific attention on ground-floor windows and any window that could be reached from outside. A window with strong locks but a handle that can be broken or manipulated to release the mechanism is a vulnerability. Key-operated handles or handles with a restricted opening mode, which allow ventilation but prevent the window opening wide enough for entry, are worth considering for accessible locations. Some insurance policies specifically recommend or require key-operated window handles on ground-floor and accessible windows.

Hinges are frequently overlooked in security conversations. Most casement windows are hinged on one side, and the hinge side can be a weak point if the hinges are not designed with security in mind. Look for hinges that incorporate anti-jemmy features, typically a pin or hook mechanism that engages when the window is closed and prevents the hinge side being forced open even when the locking mechanism is intact. Hinge bolts fitted into the frame offer similar protection on older windows being upgraded rather than replaced.

Practical tip, ask your installer to walk you through the locking points, handle operation, and hinge design for the specific product being quoted, and request that this information is included in the written specification rather than just discussed verbally.

What to Ask Your Window Installer Before You Sign Anything

Choosing the right product is only half the challenge. The quality of the installation itself determines whether a security-rated window performs as tested, and the credentials of the installer determine whether you have legal protection and documentation when the job is complete.

Begin by asking for documentary evidence of PAS 24 compliance for the specific window model being quoted. A reputable installer should be able to produce the test certificate or direct you to the manufacturer’s website where accreditation details are published. If an installer is vague, says “it meets the standard” without being able to produce evidence, or refers you to general marketing materials rather than test documentation, treat that as a warning sign and press for specifics.

Check whether the installer belongs to a competent person scheme. FENSA (Fenestration Self-Assessment Scheme) and CERTASS are the two main schemes covering window and door installation in England and Wales. Membership means the installer has been assessed as competent and is authorised to self-certify that their work complies with Building Regulations, importantly, this provides you with a legally recognised completion certificate. Without this certificate, you may face complications when selling your property, and a buyer’s solicitor is likely to flag the absence of it.

Ask whether the windows being quoted are Secured by Design licenced products, and request that this is confirmed in writing on the quotation document. A verbal assurance that is later impossible to verify has no practical value if a dispute arises.

Have a conversation about the specific layout of your home. A thoughtful installer should be recommending higher security specifications for ground-floor windows, windows in side returns that are screened from the street, windows adjacent to flat roofs or outbuildings, and windows in rooms that contain high-value items. A one-size-fits-all specification that treats every window in the house identically regardless of location and accessibility suggests the installer is not thinking about your home’s actual risk profile.

FENSA and CERTASS explained, what completion certificates mean for homeowners

Practical tip, before signing any contract, request the full written specification including the product name and range, PAS 24 test reference, glazing specification, and confirmation of whether the installer is FENSA or CERTASS registered. Keep a copy with your home documents.

How Window Security Ratings Affect Your Home Insurance

The relationship between window security standards and home insurance is more significant than most homeowners realise, and it operates in two directions, it can benefit you if your windows meet recognised standards, and it can work against you if they do not.

Many UK home insurers offer reduced premiums or improved policy terms when windows and doors meet PAS 24 or hold Secured by Design certification. The reasoning from the insurer’s perspective is straightforward, a property with windows that have been independently tested to resist forced entry is a lower risk of a successful burglary claim. In 2026, with energy improvements and security upgrades increasingly factored into residential property assessments, it is worth contacting your insurer directly before purchasing replacement windows to ask what documentation they will accept as evidence of compliance and whether premium discounts are available for PAS 24 or SbD-certified installations.

The more sobering aspect of the insurance relationship is that some policies contain clauses requiring windows and doors to meet minimum security standards. If a burglary occurs through a window that does not meet the standard specified in your policy, an insurer may have grounds to dispute or reduce a claim. This is not universal, and policy wording varies considerably between providers, but it is a genuine risk worth investigating. Read your policy documents carefully and, if the wording is unclear, ask your insurer or broker directly whether a window security standard is specified as a condition of cover.

For homeowners in areas with higher recorded burglary rates, installing Secured by Design windows is worth raising explicitly with a broker at renewal. The evidence base for SbD-certified products reducing burglary rates is well established, research supported by the police initiative itself has consistently shown that properties fitted with certified products experience lower rates of successful entry, and some insurers will recognise this when pricing a policy.

Keep all documentation from your window installation in a safe and accessible location. This means the PAS 24 test certificate or manufacturer’s accreditation reference, the FENSA or CERTASS completion certificate, and any written confirmation from the installer that the product is Secured by Design licenced. These documents matter both for insurance purposes and when you eventually sell the property, a buyer’s solicitor will typically request evidence that window and door replacements were installed compliantly.

Practical tip, contact your home insurer before completing the purchase to confirm which standards they recognise, what documentation they require, and whether a discount or improved terms are available for PAS 24 or Secured by Design installations.

Realistic Costs for Security-Rated Windows

A common concern among homeowners is whether security-rated windows carry a significant price premium over standard products. In practice, the cost difference between a basic window and a PAS 24-compliant product from a reputable manufacturer is much smaller than many people expect, and considerably less than the financial and emotional cost of a successful burglary.

These figures represent installed costs including supply, fitting, and disposal of old windows, and are based on typical UK market rates in 2026. Costs will vary depending on window size, configuration (casement, tilt-and-turn, or sash), the number of windows being replaced, regional labour rates, and whether additional work such as rendering or internal decoration is required after installation.

The price difference between a basic uPVC window and a PAS 24-compliant equivalent from the same manufacturer is often in the region of £80 to £150 per window, a relatively modest uplift when spread across a full house replacement. Secured by Design products sit at the upper end of the uPVC market or at the entry level of aluminium pricing. This reflects the additional testing, licencing, and hardware requirements, but they remain well within reach for most homeowners undertaking a full window replacement programme.

Grant funding available through schemes such as the Great British Insulation Scheme and ECO4 in 2026 is directed primarily at insulation and heating upgrades rather than window replacement. Windows are eligible under some ECO4 pathways when they are single-glazed and being replaced with double or triple glazing in lower-income households, but the grant does not specifically target the security specification. Homeowners using grant-funded window replacements should still ensure that PAS 24 compliance is written into the specification, a funded installation of non-security-rated windows is a missed opportunity.

energy efficiency grants available for UK homeowners in 2026

Practical tip, when comparing quotes from multiple installers, ensure each quote specifies the same security standard. A cheaper quote that omits PAS 24 is not a like-for-like comparison with one that includes it, and the true cost difference between the two options is almost always smaller than the headline price gap suggests.

Understanding window security ratings in the UK does not require a technical background, it requires asking the right questions of the right people before you commit to a purchase. PAS 24:2022 and Secured by Design are the two standards that matter most for homeowners in 2026, both are backed by genuine independent testing, and both are accessible enough that any reputable installer should be able to demonstrate compliance without hesitation. The windows in your home are both a thermal barrier and a physical security barrier, there is no good reason to invest in one function while neglecting the other.