"Is it secure?" is one of the first questions a customer asks about a new window or door — and the answer comes down to two names that get used loosely: PAS 24 and Secured by Design. They're related but not the same, and on new-build work one of them is the law. Here's what each actually means so you can spec with confidence and answer the question straight.
The short answer
PAS 24 is the security performance standard a window or door is tested to. Secured by Design (SBD) is a police-backed accreditation scheme that requires PAS 24 and more. Approved Document Q is Building Regs — it makes PAS 24-level security a legal requirement on new dwellings.
PAS 24 — the performance standard
PAS 24 is a British publicly available specification that sets out enhanced security requirements for doorsets and windows. To pass, a product is put through a series of tests that simulate how an intruder actually attacks: mechanical loading on the locks and hinges, manipulation tests on the hardware, and physical "cutting and levering" attacks with hand tools against the frame, glazing and locking points. If the product resists all of it within the test limits, it's PAS 24 certified.
Crucially, PAS 24 tests the whole assembly — frame, glazing, locking, hinges and beading working together. That's why you can't make a window PAS 24 by swapping in one "secure" component; the certification belongs to the tested configuration. Fit it as tested and the certificate stands.
Approved Document Q — where it's the law
Approved Document Q covers security in new dwellings in England. It requires that easily accessible windows and doors — ground floor, basement, and anything reachable from a flat roof or similar — are made to a security standard, and PAS 24 is the recognised way to show compliance. So on any new-build or new dwelling created through conversion, PAS 24 isn't optional: it's how you satisfy Building Control. Replacement work in existing homes isn't caught by Q, but customers increasingly ask for the same standard anyway.
Secured by Design — the accreditation on top
Secured by Design is the official police security initiative. An SBD product has to be PAS 24 certified as a baseline, but the scheme goes further — the manufacturer's processes are assessed, and SBD covers the wider picture of designing out crime. For your customer, an SBD product carries the reassurance of a police-backed logo; for specification on housing schemes and some insurance requirements, SBD is often the target rather than PAS 24 alone.
| PAS 24 | Secured by Design | Approved Document Q | |
|---|---|---|---|
| What it is | Test standard | Accreditation scheme | Building Regulation |
| Backed by | BSI specification | UK police | Law (England) |
| Requires PAS 24? | — | Yes, plus more | Yes, as the route to comply |
| When it applies | Any product | When specified | New dwellings |
What actually makes a window or door secure
The certification reflects the engineering, and the engineering is mostly in the hardware and glazing, not the frame material — aluminium, uPVC and composite can all achieve PAS 24. What earns the pass is the combination of a multi-point locking system, a good cylinder (anti-snap, anti-bump, anti-drill), robust hinges, laminated or toughened glazing where needed, and secure beading so the glass can't be removed from outside. Spec those as a set and the security follows.
How to steer the conversation
- New-build or new dwelling: PAS 24 is required — non-negotiable.
- Customer wants police-recognised reassurance: specify Secured by Design.
- Insurance or scheme requirement: check whether they want PAS 24 or SBD specifically.
- Standard replacement, security-conscious customer: PAS 24 gives them new-build-grade security.
- Always: fit it as tested — the certificate covers the configuration, not the parts in isolation.
Everything across our window and door ranges can be specified to PAS 24, with Secured by Design options where a job calls for it. Tell us the standard the job needs and we'll make sure the certification and the hardware are right on the order — so you can answer "is it secure?" with a certificate, not a shrug.
