Last updated: 14 July 2026
TL;DR — A window restrictor limits how far a window opens — to 125mm or less for NSW compliance — while still letting the room breathe. Installed properly, with hardware that holds 250 newtons, it is the difference between a window a child can fall from and one they cannot. Haven installs REMSAFE restrictors across Sydney, matched to your window type, force-tested on the spot, and documented so your building’s register is updated the same day. Fixed per-window pricing: call +61 2 8000 0287.
A restrictor is a device — cable, chain, stay or track-limiting mechanism depending on the window — that stops a window opening beyond a set gap. For NSW strata compliance the gap is 125mm or less, and the device must resist 250 newtons of force under the AS 5203:2016 test method.
You need restrictors wherever section 118 applies: openable windows with the internal floor two metres or more above outside ground and the opening starting below 1.7 metres. Outside strata — houses, townhouses, childcare-adjacent properties — the same hardware is the voluntary gold standard for child safety.
Both can comply; they solve the problem differently. A restrictor permanently limits the opening while allowing airflow — ideal for bedrooms and living areas where ventilation matters.
A lock secures the window shut or at a keyed position — often suited to ground-contact security or windows rarely opened. The right choice is window-by-window, not building-by-building, and our restrictors-versus-locks guide covers the decision in detail.
In practice, most Sydney buildings end up with a mix, which is why our installers carry both and decide with you at the window, not from a brochure.
We install REMSAFE window safety hardware — restrictors and locks engineered for the Australian market and the 250 newton requirement. Every device we fit is matched to the window type it protects: awning, sliding, double-hung, casement and louvre windows each take different solutions, and the wrong device on the right window fails the test as surely as no device at all.
After fitting, each device is force-tested and photographed. You are not buying hardware in a box; you are buying a window that provably complies.
For a single unit: minutes per window. The installer confirms which windows qualify, fits the device appropriate to each window type, force-tests it, and leaves every window operable — restricted where the law requires, fully openable by an adult where the design allows re-engagement.
For whole buildings, installation runs off the audit register: units are scheduled in sequence through the strata manager’s access process, occupied units handled with standard entry notices, and the register updated as each unit completes. Most residents notice nothing except a new device that works smoothly.
Pricing is per window, fixed before we start, and shaped by device type and window access. The assessment that scopes the work runs at Haven’s standard rates (a single property is $250 + GST, buildings of 2 to 10 units are $490 + GST, and buildings of 11 or more units are quoted on request — fixed before booking, with the digital compliance certificate delivered the same day), and hardware supply-and-installation is quoted fixed per window on top.
Two honest cost notes. Combining installation with the initial audit visit is cheaper than separate call-outs. And bargain online hardware is a false economy — devices that have never been verified against 250N fail their next inspection, and you pay for the window twice.
Sydney’s building stock uses five common window types, and each takes a different compliant solution: Awning windows — hinged at the top, opening outward: chain or stay restrictors that arrest the sash at 125mm. Sliding windows — the most common in post-war apartments: track-mounted limiters or keyed locks that stop the sash at the compliant gap.
Double-hung windows — classic in older walk-ups: sash-mounted restrictors or dual screws/stops limiting vertical travel; older timber frames need fixings chosen for the material’s condition. Casement windows — side-hinged: friction stays or cable restrictors rated for the outward leverage these windows generate.
Louvres — a special case: individual blades rarely create a 125mm opening, but where they do, robust screens are usually the practical fix. This is why a hardware-store one-size device so often fails: the physics of an awning window and a slider are different problems.
Matching device to window — and fixing into sound material — is the installer’s actual craft.
Installation ends with proof, not just hardware. Every device is force-tested against the 250 newton requirement at the window it protects, photographed, and logged into the building’s compliance register — so the owners corporation’s records show not only that devices exist but that each one was verified working on a stated date.
Residents notice almost nothing: windows still open for ventilation to the compliant gap, adults can still release devices for cleaning where the design allows, and the hardware sits as unobtrusively as the window furniture it joins. What changes is invisible until it matters — the window that could have been a fall is now a window that cannot be.
For buildings on our maintenance cycle, these same devices are rechecked each year and retightened or adjusted before small wear becomes a failed test.
Yes, where the device design allows release — an adult can disengage it for cleaning or full ventilation, and the restrictor must then be re-engaged. Children cannot operate the release.
There is a compliant solution for every common window type — awning, sliding, double-hung, casement and louvre — but they are different devices. Matching hardware to window type is most of what separates a passing installation from a failing one.
Physically, often yes; provably, rarely. Compliance turns on the 125mm gap and the 250 newton hold, and DIY installations are almost never force-tested or documented. For a strata building, professional installation with test evidence is the defensible path.
Minutes per window once on site. A typical unit is completed in a single short visit; whole buildings are scheduled unit-by-unit off the audit register.
Yes — every installed device is force-tested, photographed and entered into the building’s compliance register, with completion evidence supplied for the scheme’s section 180 records.
Need restrictors fitted — one unit or a whole building? Haven installs force-tested REMSAFE hardware across Sydney with fixed per-window pricing. Call +61 2 8000 0287 or email admin@havencompliance.com.au.
