Two Points Are Actually Attacked

A tilt-turn window with a multi-point lock is sold as a security system, and on paper it is one. In practice a burglar does not attack a window the way a rating table describes. The rating describes time-to-defeat of a whole assembly under sustained, tool-based attack. The burglar attacks the two points where that time collapses, and on a tilt-turn window those two points are the profile cylinder on the handle side and the hinge side where the sash can be lifted or removed. Harden one of the two and the attack simply moves to the other.

What makes a tilt-turn window different from a casement is that the sash exists in two positions — tilt (top edge released, bottom on the stay) and turn (hinged, full opening) — and the security of the sash in each position is provided by different hardware. A sash in tilt is held at the bottom by the stay and is only partially locked, so it is a different target from the same sash in the closed, multi-point-locked turn position. Most security specifications address the fully closed position and say nothing about the tilt position, which is exactly the position a burglar works in first, because it is the easiest.

This article sets out the cylinder attack and the hinge-side attack separately, the specific hardware that resists each, how the glass fits into the time calculation, and what to specify so that no single cheap element caps the class you paid for.

The Cylinder Attack, by Method

The order of rows is roughly the order in which a determined attacker tries them, and it is worth reading carefully. The drill row is the one that matters most for a tilt-turn window, because it is fast, it needs only a small power tool, and it targets the exact point where the multi-point lock is anchored. A hardened core and a drill plate over the gearbox move the drill attack from seconds to several minutes, and those several minutes are what an RC rating is built on.

The Hinge-Side Attack, by Method

The hinge side of a tilt-turn sash is where the sash connects to the frame and where it can be separated. The attack here is not about the lock at all; it is about removing the sash from its running so that it can be turned off its hinges.

Why the Tilt Position Is the First Move

In the tilt position the top of the sash is released and the bottom rests on the stay. The multi-point lock is not engaged in the way it is when the sash is fully closed and turned. A burglar who reaches a tilt window therefore has a sash that is already half out of its secure running, held in place by a stay rather than by a lock. The stay is a mechanical device, not a lock, and it is not designed to resist sustained forced entry.

Two design requirements follow. First, the sash must not be removable while in the tilt position; the stay geometry and the hinge arrangement should keep the sash engaged in the bottom rail so that it cannot be lifted and turned off. Second, the window must be specified so that the tilt position is not an invitation to entry. A window that locks to RC2 in the closed position but whose sash can be lifted and removed in the tilt position does not have an effective RC2, because the burglar does not have to defeat the closed-position lock at all.

This is the point that most security quotations miss, and it is the point to put in the specification in plain words: state the class for the closed and locked position, and state separately that the sash is not removable in the tilt position.

Sash Lift and Rebate Depth

The sash lift attack works by lifting the sash vertically until it clears the bottom rail rebate, then swinging it off the hinges. Whether this is possible depends almost entirely on the depth of the rebate and on whether there are anti-lift pins or stops.

• A shallow rebate leaves little for the sash to be lifted against. If the vertical clearance at the bottom rail is small, the sash can be lifted out and turned off with a bar or a pry. The rebate depth is a structural detail of the frame, and it is not something that can be fixed after the frame is made.
• Anti-lift pins or stops in the bottom rail physically prevent the sash from being lifted clear. They are small, cheap, and they convert a sash lift from a viable attack into a non-starter. They belong in any security specification.
• The hinge pins themselves must not be removable from the outside. A standard lift-the-pin hinge is defeated in one motion. Concealed or non-removable pins, or a hinge with a locking element, remove that motion entirely.

The Mitred Corner Under a Pry Bar

Where the frame corners are mitred and the sash sits against the seal, a pry bar at the corner applies a prying force that the seal and the corner joint have to resist. This is not a seal problem and not a lock problem; it is a joint problem. A mitred and cleated corner holds, but a poor mitre, or a mitre without adequate cleating, opens under prying and the sash can be levered away from the seal on that side.

Welded corners are the stronger detail for security, because there is no mitre joint to open. Where the corners are mitred, specify the cleating and, where the security class is RC3 or higher, ask for corner reinforcement. This is a small cost that protects against one of the four physical attacks on the sash.

The Glass Is the Final Barrier and Often the Deciding One

The frame, the cylinder and the hinges are attacked in minutes. The glass is attacked in a time that depends entirely on its build, and that time often dominates the overall RC rating. If the glass is the slowest element, then the window holds the class because the glass holds it, and a cheap glass specification will cap the rating no matter how well the hardware is protected.

The side of the glazing matters too. In an external attack the laminated layer should face the attacker, so that the first pane to break is the one with the interlayer holding the fragments. A laminate put on the wrong side still holds, but it holds the wrong fragment and the attacker is working on a clean break. Where the glass is in a low zone or a reachable position, the laminated or toughened choice is also a safety requirement, and the two purposes are served by the same build.

How the RC Rating Is Actually Built

EN 1627 defines forced entry classes by the time a trained attacker with defined tools needs to defeat the whole assembly — frame, glass and hardware together. The class is not a rating of the lock alone; it is a rating of the path of least resistance through everything in the window.

The consequence is a weakest-link result that procurement teams find uncomfortable. A window can be specified with an anti-bump, anti-snap, drill-resistant cylinder, non-removable hinges and anti-lift pins — and still rate only RC1, because the glass is a simple insulated unit that a brick breaks in under three minutes. The hardware class and the glass class are added together in time, and the sum is the window class. When the sum is dominated by the glass, spending on the hardware beyond a certain point buys nothing, and vice versa.

The UK adds PAS 24 and Secured by Design, which are design standards rather than attack-time ratings, and which a security window may need in addition to its RC class. Ask which of the two applies to the destination, because a window can be RC2 and still not be PAS 24 compliant, and can be PAS 24 and not carry an RC test at all.

Integration With an Alarm

A window can be physically strong and still give the occupant no warning that it has been defeated. For that reason a security specification that includes an alarm should name the sensing, and the sensing has to match the attack.

• A magnetic contact on the sash breaks when the sash moves away from the frame, so it detects a sash turned open and a sash lifted off. It does not detect a glass break where the sash stays in its frame.
• A glass-break sensor detects the break event but not the sash removal. A sash lifted off its hinges does not break the glass and so does not trigger it.
• The two are complementary, not redundant. A perimeter alarm on the sash plus a glass-break sensor covers both the sash-removal path and the glass path. A glass-break sensor alone is the most common and most incomplete choice.
• Where the window is automated, the sash open/closed and tilt/turn state should be reported over RS485/Modbus or KNX to the building management or alarm system, so that a sash left in tilt, or forced open, is logged rather than merely audible on site.

What to Standardise and What to Localise

Specification Checklist

1. Which security class is required — an EN 1627 RC class, a PAS 24 design standard, or a project specification — and is the rating for the whole assembly including the glass?
2. Which cylinder is specified — anti-bump, anti-snap, drill-resistant — and does it carry the recognised mark for the destination?
3. How is the cylinder fixed, and is the fixing a security screw rather than a standard head?
4. Are the hinge pins non-removable or concealed, and can the sash be removed from the outside in any position?
5. Is the sash removable in the tilt position, and if so, is that acceptable for the class being quoted?
6. Are there anti-lift pins or stops in the bottom rail, and what is the rebate depth?
7. Are the frame corners mitred and cleated or welded, and is there corner reinforcement for RC3 or higher?
8. What is the glass build, is the laminated layer on the external face, and does its break time match the class rather than the hardware?
9. What alarm sensing is provided — magnetic contact, glass-break, or both — and is the sash state reported over RS485/Modbus or KNX?
10. What fixing and pin grade is supplied, and is SUS316 required for the exposure?

Manufacturing and Verification Chain

2026 Indicative FOB Prices and Security Adders

Prices are indicative 2026 factory FOB ranges for project volumes, excluding freight, site installation and alarm system integration. Security adders are cumulative and are meaningful only relative to the glass build, because the class is the sum of the frame, hardware and glass attack times. A higher hardware specification without a matching glass build will not raise the class. Final quotation depends on the destination class or design standard, the cylinder mark, the hinge and anti-lift detail, the corner detail, the glass build, the alarm interface, and the documentation package required. Contact Rogenilan Windows Doors for a class-specific hardware and glass calculation.

Security FAQ for Tilt-Turn Windows

Why does a window with a strong lock still fail a security test?

Because the test attacks the path of least resistance through the whole assembly, not the lock. If the glass breaks in under the attack time the class requires, the window fails the class even with a drill-resistant cylinder and non-removable hinges. The rating is a sum of the frame, hardware and glass, and the weakest element sets the result.

What is the point of a multi-point lock if the sash can be lifted off?

It has no point, and that is the specification error. A multi-point lock secures the sash in its running. If the sash can be lifted clear of the bottom rail or removed at the hinge, the lock is defeated without being attacked. The anti-lift pins and non-removable hinges exist to close exactly that gap, and they must be specified together with the lock, not instead of it.

Does a window need both an RC class and PAS 24?

In the United Kingdom it commonly does, because RC is an attack-time rating and PAS 24 is a design and hardware standard, and a scheme may require one or both. In the rest of Europe the RC class is the usual requirement. State the destination and the applicable standard before quotation, because a window can be RC2 and not PAS 24, and can be PAS 24 without an RC test.

Why does the laminated layer face matter?

Because the pane with the interlayer should be the one the attacker breaks first, so the fragments are held on the outside and the attacker is working on a surface that resists penetration. A laminate on the wrong side still holds the pieces, but it holds the wrong side and gives up a cleaner break to the attacker.

Can a burglar remove the sash in the tilt position?

Only if the stay and hinges allow it. In a well-designed security sash the tilt position is not removable: the sash stays engaged in the bottom rail on the stay and cannot be lifted and turned off. This is a requirement to state in the specification, because many standard tilt-turn units are removable in tilt and are then not as secure in that position as the closed-position rating suggests.