How to childproof windows: by window type, with the five CPSC rules and the guard install

The five CPSC rules

The CPSC's window safety release lists them, and they are the framework for everything below. Install window guards. Never depend on screens to keep children from falling out. Install stops so windows open no more than four inches. Keep furniture away from windows to discourage climbing. Open windows from the top instead of the bottom whenever possible. The numbers behind the rules, from the same release: an estimated 5,600 children aged 12 and under treated in emergency departments in 2024 after a window fall, about one in three hospitalized, and at least 25 deaths from 2021 to 2023, 80 percent between May and October. The products are ranked in best window guards and locks.

Double-hung and single-hung

The window with a sash that slides up. Open it from the top if it is double-hung; a top opening is out of reach and a bottom opening is a step. For the lower sash, either a stop or a guard. The Cresci Window Wedge is a Velcro-mounted adjustable stop for hung and sliding windows: set it so the sash rises no more than 4 inches, press it to the frame, done. A guard across the opening lets you open the window all the way with the bars in place; that is the choice for a window you use for air in a toddler's bedroom. The two are compared in window guards vs window stops.

Horizontal sliders and patio doors

A slider has a track, and the fix is something in the track. KidCo's S3392 sliding lock mounts on the frame and extends a latch into the sash's path; squeeze and slide to retract it. The Window Wedge also works in a slider track. For a sliding patio door, the same track lock plus, if the door leads to a pool or a yard with water, a door alarm; the pool layers are in how to childproof a pool. Guardian Angel's guards can also be installed vertically across a slider, which is the answer when you want the slider fully open with a screen's worth of air.

Casement and awning

Crank-out windows have no track for a stop and open outward from the bottom, which makes them the easiest window for a child to fall from once open. Two fixes: a guard across the inside of the opening (bars vertical or horizontal per the maker), or remove the crank handle and keep it in a drawer so the window cannot be opened by a child at all. Some casement makers sell opening limiters; ask for one by the window brand. Awning windows (hinged at the top, opening outward at the bottom) get the same treatment.

Installing a guard

The steps are in the box above. The two that matter: buy the end-post height that covers the window's maximum opening (Guardian Angel publishes 13, 17.375 and 21.75 inch posts for 17.25, 21.5 and 26 inch openings), and test the emergency release with every adult present, because a guard nobody can open in a fire is the failure the ASTM F2090 standard was written to prevent. Then move the crib: the CPSC's furniture rule is the one that costs nothing, and the crib under the window is the arrangement the fall data keeps describing. The other window hazard, the blind cord, is in blind cord safety.

The picks

Two window jobs have their own pages. A crank window takes none of the stops above, and the fixes that do work are on how to childproof casement windows; fitting a guard properly, including which frames hold a screw, is on how to install window guards.

The biggest sliding panel in most houses is not a window at all. A patio slider needs a track lock, a second lock out of reach and, next to water, an alarm: how to babyproof a sliding glass door.