PAS 24 Security Windows and Doors: Physical Attack Standards Explained
PAS 24 (Enhanced security performance requirements for doorsets and windows in the UK) is the benchmark British Standard governing forced-entry resistance across residential and commercial fenestration. It establishes rigorous laboratory test methods and mechanical performance criteria to verify that complete window and doorset assemblies resist opportunistic burglar attacks using heavy hand tools, including crowbars, chisels, screwdrivers, hacksaws, and mechanical impact rammers. Unlike component-level tests that evaluate an isolated cylinder or hinge, PAS 24 tests the complete fabricated unit: the outer frame, sash profile, internal reinforcement, glass retention system, hardware gearboxes, keeps, and perimeter fixing anchors.
Under England and Wales Building Regulations, Approved Document Q (Security in Dwellings) mandates that all easily accessible doors and windows installed in new dwellings must satisfy PAS 24 or an equivalent physical attack standard. This legal requirement applies to newly built residential homes, apartment complexes, and change-of-use conversions from commercial buildings to residential dwellings. Accessible openings include all ground-floor and basement apertures, alongside any window, rooflight, or terrace door situated within 2 metres of an accessible flat roof, balcony, retaining wall, or external staircase.
3.0 kN Mechanical Load
Hydraulic ram pressure applied to lock points, hinge stiles, and glass rebate corners.
50 kg Impact Impactor
Soft-body sandbag and hard-body steel drop pendulum testing structural frame rigidity.
TS007 3-Star Cylinder
Sacrificial snap cuts, molybdenum bridges, and hardened pins resisting cylinder attack.
BS EN 356 Class P1A
Minimum 6.8 mm laminated glass with polyvinyl butyral interlayer preventing smash entry.
Key Regulatory Benchmark: PAS 24:2022 and Approved Document Q
- PAS 24:2022 is a full-assembly product testing standard applying to uPVC, aluminium, composite, and engineered timber systems.
- Approved Document Q mandates PAS 24 or equivalent on all easily accessible windows and external doorsets in new dwellings, flat developments, and residential conversions.
- Laboratory testing enforces manipulation probing, 3 to 15 minute manual attacks with chisels and levers, 3.0 kN hydraulic loading, and 50 kg dynamic impact swings.
- Glass specification under Document Q requires accessible glazed units to incorporate at least one pane of BS EN 356 Class P1A laminated security glass (minimum 6.8 mm total thickness).
- Core hardware requisites include internal security beading, bidirectional shootbolts with mushroom cams, hinge security dog bolts, and TS007 3-star anti-snap lock cylinders.
The Four Rigorous Physical Attack Tests of PAS 24:2022
To secure PAS 24 certification, sample window and doorset assemblies are mounted into rigid steel test rigs at a UKAS-accredited testing facility. Testers then execute four distinct, sequential attack phases designed to replicate the full spectrum of modern forced-entry methods used by burglars.
Phase 1: Manipulation Attack Test
Before using noisy heavy tools, testers spend dedicated time attempting to bypass the locking system silently. Using thin metal probes, feeler gauges, craft knives, and flexible wires, they attempt to trip spring latches, slide back lock bolts, unclip external gaskets, or remove external glazing beads. If any tool bypasses the locking hardware or releases the glass pane without causing structural damage, the unit fails immediately.
Phase 2: Manual Tool Attack Test
Experienced laboratory technicians attempt to create an aperture through which an intruder could enter or manipulate an internal handle. Using tool kits containing heavy screwdrivers, wood and cold chisels, pry bars, and hardwood wedges, testers apply aggressive prying pressure to the sash corners, hinge stiles, locking points, and central meeting rails. The attack runs for timed periods ranging from 3 to 15 minutes of direct physical contact. The assembly passes only if the sashes remain firmly locked and no 225 mm by 380 mm elliptical opening can be formed.
Phase 3: Mechanical Infill Loading Test
Following manual attacks, the test sample is subjected to mechanical loading using hydraulic rams. A perpendicular load of 2.0 kN to 3.0 kN (approximately 200 kg to 300 kg of force) is applied directly to each corner of the glazed unit and to the operating sashes. A parallel shearing load of 1.5 kN is simultaneously applied to verify that the glass unit cannot be pushed out of its internal rebate. The frame profiles, internal glazing beads, and glass retention clips must hold the sealed unit securely without dislodgement.
Phase 4: Dynamic Hard and Soft Body Impact Tests
The final phase evaluates resistance against violent physical impacts, such as body-slamming, kicking, or battering ram strikes. A 50 kg soft-body sandbag pendulum impactor is swung from specified drop heights directly at the centre of the door slab, window infill panels, locking gearboxes, and corner joints. In doorset evaluations, a 30 kg hard-body steel drop impactor is dropped onto vulnerable lock points. The unit must absorb the kinetic energy without catastrophic frame fracture or hardware separation.
| PAS 24:2022 Test Phase | Testing Apparatus & Tooling | Duration & Applied Force | Pass Criteria & Structural Standard |
|---|---|---|---|
| Manipulation Test (Clause B.4.3 / C.4.3) | Feeler gauges, craft knives, wire hooks, paint scrapers | 3 to 5 minutes total contact time | Zero hardware bypass, unlatching, or bead release without noise |
| Manual Tool Attack (Clause B.4.4 / C.4.4) | Cold chisels, 300 mm screwdrivers, levers, hardwood wedges | 3 to 15 minutes manual prying pressure | No entry aperture exceeding 225 mm by 380 mm created |
| Mechanical Loading (Clause B.4.5 / C.4.5) | Hydraulic ram pistons with calibrated load cells | 2.0 kN to 3.0 kN perpendicular, 1.5 kN parallel | Infill panel and glass unit remain retained within rebate |
| Dynamic Body Impact (Clause B.4.6 / C.4.6) | 50 kg sandbag pendulum and 30 kg steel impactor | Multiple pendulum drops from 800 mm height | Frame remains latched and secure; no corner weld separation |
Engineering Anatomy of PAS 24 Windows and Doorsets
Achieving PAS 24 compliance requires high-grade hardware, rigid multi-chamber profile engineering, and specialized glazing methods working in coordination. If any single element fails, the entire window or doorset will buckle under hydraulic or manual attack.
Internal Security Glazing Beads
Older window designs placed glazing beads on the external face of the frame. An intruder with a common putty knife or screwdriver could lever off the external beads in under 60 seconds and lift out the entire double-glazed unit without making sound. PAS 24 windows solve this vulnerability through internal glazing beading. The bead clips into an internal retention channel located within the room. It is physically impossible to access or de-clip the glazing beads from the outside elevation. For additional rigidity, commercial systems feature security glazing clips or adhesive bonding tape between the glass unit and the sash rebate.
Multi-Point Locking with Bidirectional Shootbolts
Standard residential windows often rely on simple single-point cockspur handles or basic espagnolette rollers. PAS 24 casement windows use heavy-duty multi-point gearboxes driving bidirectional steel shootbolts into reinforced corner keeps. Alongside shootbolts, hardened mushroom cams travel in opposing directions to clamp into heavy-gauge steel keeps anchored into the outer frame reinforcement. When an intruder attempts to force the opening sash with a crowbar, opposing cams lock tighter into their keeps, neutralizing lateral and perpendicular prying forces.
Hinge Security Claws and Interlocking Dog Bolts
Burglars frequently target the hinge side of outward-opening windows and doors, attempting to chisel off the hinge knuckles or lever the sash away from the frame. PAS 24 assemblies incorporate solid steel interlocking security claws, commonly known as dog bolts. Mounted directly to the sash stile, these heavy steel studs engage deeply into matching reinforced sockets in the outer frame when the sash closes. Even if an attacker cuts through external hinge pins, the dog bolts keep the sash rigidly locked within the frame aperture.
TS007 3-Star Cylinder Protection
Lock snapping is the primary method used to attack residential entrance doors across the UK. Standard euro cylinders can be snapped in half using mole grips or claw hammers in less than 10 seconds, exposing the internal lock gearbox. PAS 24 entrance doors eliminate this risk through TS007 3-star high-security protection. This is achieved either through a dedicated 3-star anti-snap cylinder (featuring sacrificial external snap sections, a hardened molybdenum core bridge, and anti-drill pins) or a 1-star cylinder combined with a 2-star reinforced security handle. If an attacker snaps the front section of the cylinder, the sacrificial line breaks cleanly while the high-tensile core remains locked deep inside the gearbox.
BS EN 356 Class P1A Laminated Security Glass
While toughened safety glass satisfies Approved Document K by crumbling into harmless granular pieces upon impact, it offers minimal forced-entry resistance once shattered. Under Approved Document Q, accessible doorsets and windows must incorporate at least one pane of BS EN 356 Class P1A laminated security glass. Laminated glass consists of two panes of float glass bonded together under heat and pressure with a tough polyvinyl butyral (PVB) interlayer (minimum 0.38 mm to 0.76 mm thick, producing a minimum 6.8 mm total glass thickness). When struck with bricks, sledgehammers, or crowbars, the glass fractures but remains firmly stuck to the PVB sheet, preventing intruders from creating a hole or reaching through to open internal lock handles.
Approved Document Q Compliance Across Property Types
Building Regulations compliance often causes confusion among homeowners, property developers, and builders. Approved Document Q governs security standards across residential properties in England and Wales, establishing clear boundaries on where PAS 24 compliance is legally enforceable.
| Project Classification | Document Q Legal Enforcement | Accessible Openings Scope | Mandatory Glazing & Security Specification |
|---|---|---|---|
| New-Build Residential Dwellings | Fully mandatory under Building Regulations | All ground-floor, basement, and accessible roofline openings | PAS 24 certified frames, TS007 3-star cylinders, BS EN 356 P1A laminated glass |
| Commercial to Residential Conversions | Fully mandatory (Material Change of Use) | All accessible external entrance doors and low-level windows | PAS 24 doorsets with letterplate security cowls and P1A security glass |
| Domestic Home Extensions | Subject to local building control discretion | New ground-floor bifold doors, sliding doors, and windows | PAS 24 certified door and window systems strongly recommended |
| Like-for-Like Replacements in Existing Homes | Exempt from Approved Document Q | Existing aperture replacement without altering structure | Must satisfy Approved Document L thermal efficiency; PAS 24 fitted as standard |
When executing new-build developments or conversions, building control officers will inspect test certificates and manufacturer documentation during final inspections. Failure to provide UKAS-accredited PAS 24 test reports or evidence of BS EN 356 P1A laminated glass on accessible openings will delay the issuance of the Building Regulations Completion Certificate, hindering property sales and mortgage approvals. Further details on local authority sign-offs are covered in our building control inspections guide and our comprehensive Building Regulations guide.
Secured by Design (SBD) vs PAS 24: Understanding the Difference
Many clients ask whether PAS 24 is identical to Secured by Design (SBD). While closely linked, they represent two distinct levels of verification in the fenestration sector:
PAS 24 is a British Standard physical testing protocol. A manufacturer submits representative window and doorset samples to an accredited laboratory to verify that the design meets established attack thresholds.
Secured by Design is the official police security initiative managed by Police Crime Prevention Initiatives (PCPI). SBD uses PAS 24 as its baseline technical requirement, but adds strict administrative and manufacturing criteria. To achieve SBD accreditation, a fabricator must hold an active third-party certification scheme (such as BSI Kitemark or BM TRADA Q-Mark) with regular factory audits. This ensures that every window produced in the factory matches the exact steel thickness, hardware fixing screws, and glass bonding methods of the original test sample.
For housing association developments, institutional tenders, and commercial projects, SBD specification is frequently required by architects and planning authorities. Learn more about commercial specifications in our commercial contracts guide.
Technical Surveying and Installation Protocol for Maximum Security
Even the highest-rated PAS 24 window or doorset will fail under attack if it is installed incorrectly. A 3.0 kN hydraulic ram load or a crowbar attack will easily lever an entire frame out of a brickwork reveal if the perimeter fixing anchors are loose or incorrectly spaced. Our installers follow a four-stage surveying and installation protocol on site:
Stage 1: Structural Site Survey and Diagonal Tolerances
Our surveyors check the structural masonry condition, lintel integrity, cavity closer alignment, and damp-proof course positioning. Apertures are cross-measured diagonally: squareness tolerances must remain within 2 mm of true diagonal symmetry. Fixing zones are mapped out to ensure frame anchors penetrate solid inner-leaf brickwork or blockwork rather than crumbling mortar joints or soft thermal blocks.
Stage 2: Heavy-Duty Masonry Anchor Fixing
Frames are installed using direct masonry frame screws or heavy-gauge through-frame fixings with a minimum 100 mm embedment depth into load-bearing brickwork. In accordance with BS 8213-4, corner fixings are placed between 150 mm and 250 mm from internal frame corners, with intermediate fixings spaced no further than 600 mm apart along all jambs, cills, and heads. Solid load-bearing plastic packers are positioned adjacent to every screw to prevent outer frame deflection when fixings are torqued.
Stage 3: Toe-and-Heeling and Hardware Calibration
To ensure sashes do not drop over time, double-glazed units are packed diagonally using plastic bridge packers placed beneath the bottom hinge corner and above the top locking corner (toe-and-heeling). This braces the glass unit as a structural diagonal member, maintaining sash squareness. Installers then adjust mushroom cams, roller keeps, and shootbolt throws to achieve an airtight 1.5 mm to 2.0 mm gasket compression across all perimeter seals.
Stage 4: Perimeter Sealing and Weatherproofing
Perimeter expansion gaps between the frame and masonry reveal are sealed using pre-compressed expanding foam tapes or low-expansion polyurethane insulation foam. The exterior perimeter is sealed with high-performance, low-modulus neutral-cure silicone sealant conforming to ISO 11600. This provides continuous weather tightness under Approved Document C and prevents water penetration from degrading structural wall ties.
Procurement and Sourcing Options for Builders and Homeowners
Window Fitters Ltd provides clear, flexible procurement routes for homeowners, private developers, and commercial main contractors looking to fit PAS 24 security windows and doors:
Installation-Only and Labour-Only Fitting Teams
If you are a builder or self-builder who has already sourced PAS 24 certified window frames or entrance doors directly from trade fabricators or trade counters, our professional fitting teams provide specialized installation services. We bring precision laser levels, heavy-duty masonry anchors, setting blocks, and technical glazing expertise to fit your units to strict British Standards. Review day and unit rates in our labour-only installation guide.
Sourced Trade Supply with Dedicated Installation
Under this popular procurement model, our senior surveyors conduct detailed site opening surveys and source PAS 24 certified systems directly from leading UK profile extruders (including Rehau, Profile 22, Liniar, Origin, and Cortizo) at commercial trade prices. Our certified teams fit and commission the units on site, combining trade purchasing rates with dedicated installation management.
Complete Supply and Installation Package
For private homeowners and developers seeking single-point contractual responsibility, we manage the complete process from architectural survey through custom factory fabrication, delivery, on-site installation, building control compliance documentation, and our 10-year insurance-backed guarantee. Compare procurement pathways in our supply and fit comparison guide and explore typical project pricing in our glazing installation cost guide.
Explore our full fenestration range: browse our complete external doors directory, review certified door installation services, consult our trade-certified window installers and door fitters, explore high-performance composite entrance doors, review bifold door installations, examine panoramic sliding doors, book professional window fitters, review full-house window installation, or contact our team directly for a technical survey quote.
Frequently Asked Questions About PAS 24 Windows and Doors
Explore security standards covering PAS 24 mechanical load testing, manual attack resistance, laminated safety glass, and Approved Document Q.
What is PAS 24 security certification for windows and doors? +
PAS 24 is the benchmark British Standard specifying enhanced security performance requirements for complete external window and doorset assemblies in the UK. Rather than testing individual components in isolation, PAS 24 evaluates the fully fabricated unit, including the outer frame, internal steel or aluminium reinforcement, glass retention systems, multi-point locking gearboxes, keeps, hinges, and perimeter fixings under rigorous laboratory attack conditions.
What security hardware is required to achieve PAS 24 compliance? +
To achieve PAS 24 compliance, a window or doorset must incorporate internal security glazing beads that prevent glass removal from the exterior, heavy-duty multi-point locking systems with bidirectional steel shootbolts and mushroom cams, interlocking hinge security dog bolts, and a TS007 3-star rated anti-snap lock cylinder combination that resists drilling, picking, and snapping attacks.
Is PAS 24 mandatory on all new builds and extensions under Document Q? +
Approved Document Q of the Building Regulations mandates that all easily accessible windows and external doorsets on new dwellings, including commercial-to-residential conversions, must satisfy PAS 24 or an equivalent standard. Easily accessible openings include all ground-floor and basement apertures, as well as any window or door positioned within 2 metres of an accessible flat roof, balcony, or external staircase.
What glass specification is required for PAS 24 compliance? +
Under Approved Document Q, all easily accessible doorsets and windows must incorporate at least one pane of security laminated glass certified to BS EN 356 Class P1A. This laminated pane has a minimum total thickness of 6.8 mm and features a bonded polyvinyl butyral interlayer that holds the glass sheet intact under heavy repeated hammer and lever impacts, preventing manual intrusion even if the glass is cracked.
What is the difference between PAS 24 and Secured by Design? +
PAS 24 is the technical physical attack test standard conducted in a UKAS-accredited laboratory on sample units. Secured by Design is an official UK police security initiative that adopts PAS 24 as its minimum technical baseline, but also requires manufacturers to undergo continuous third-party factory production control auditing, such as the BSI Kitemark or BM TRADA Q-Mark, to verify ongoing manufacturing consistency.
Can existing windows be retrofitted to achieve PAS 24 certification? +
Existing windows cannot be retroactively certified to PAS 24 standards. While you can upgrade individual locks, handles, or cylinders to high-security specifications, PAS 24 certification applies exclusively to the complete assembled product tested as an integrated unit, including internal profile reinforcement chambers, factory-glazed bead channels, and dedicated steel reinforcement keeps.
Author & Technical Reviewer: Marian Gheorghe
Head Installer & CEO, Window Fitters Ltd
Marian Gheorghe is the Active Director and Team Leader Installer at Window Fitters Ltd. With over 15 years of hands-on experience, he oversees technical safety and UK Building Regulations compliance for all residential and commercial glazing contracts.
Ready to discuss your project?
Window Fitters Ltd provides window and door installations across London and Surrey for residential, trade, and commercial projects.
Message our team on WhatsApp or send an enquiry with your drawings, photos, or measurements to receive a free, no-obligation quote.
Share this page on social media, whatsapp, print it or email to anyone:
Verified Google & MyBuilder Reviews
"Stunning Sash Windows in Croydon"
"Marian and his team replaced our old Victorian sash windows. They were clean, fast, and the double glazing has completely blocked out the street noise. Highly recommended!"
"Excellent Bifold Doors in Bromley"
"Installed beautiful grey aluminium bifold doors for our new kitchen extension. Smooth gliding mechanism and great insulation. The best quote we got in Kent."
"Perfect Front Door Upgrade in Sutton"
"Very happy with our new composite door installation. Excellent lock security and high-quality GRP slab finish. Fast half-day fitting and no mess left behind."