You rent a ground-floor apartment, and the bedroom window faces a shared walkway. You want security window bars, but you also need a way out if there is a fire. Both goals are possible, but only if you match the right bars to the right window.

Security window bars are rigid steel bars mounted over a window opening. They attach to the window frame, to the wall around it, or inside the window recess. They add a physical barrier, so anyone trying to reach through or climb in has to defeat the bars first. That takes effort and makes noise. No bar makes a home impossible to enter, and bars do nothing for a weak door or an unlocked entry.

People search for the same product under several names: security window bar, window security bar, or indoor security window bars. Indoor versions mount inside the room, usually in the recess, so the outside of the building changes less. That can matter if you rent, but ask your landlord before you drill into anything.

The real question is not only 'will this slow a break-in?' It is also 'can everyone inside get out through this window?' Our complete guide to window security bars covers the basics. This post focuses on choosing bars that open when they have to.

Not all bars behave the same way when you push on them from inside. The table below groups them by how they release. It describes categories, not specific products.

'Window security bars that open' can mean two different things. You may want to open the window for fresh air with the bars in place. Or you may want the bars themselves to open so you can climb out. Bars mounted over a window can let the sash open for air, depending on the window type and how the bars attach. Only a release you can operate from inside addresses escape.

See how the main styles differ in our overview of types of window bars. Before you buy, decide which of the two meanings applies to each window.

If the window is a required escape opening, yes. The 2021 IRC, section R310.1, requires at least one operable emergency escape and rescue opening in basements, habitable attics and every sleeping room, with limited exceptions such as basements used only for mechanical equipment. Section R310.1.1 says it must be operable from inside "without the use of keys, tools or special knowledge." The Boulder County building guide on emergency escape and rescue openings summarizes these rules.

The same guide covers bars directly. Under R310.4.4, bars, grilles, covers and screens over escape openings or area wells must leave the required net clear opening. They must also be "releasable or removable from the inside without the use of a key or tool or force greater than that required for the normal operation of the escape and rescue opening." The size rules include a net clear opening of at least 5.7 square feet (5 square feet at grade floor), a clear height of at least 24 inches, a clear width of at least 20 inches, and a sill no higher than 44 inches above the floor.

Section numbers change between editions, and your city or county may adopt different rules. Always say '2021 IRC' when you compare, then confirm with your local building department.

Fire safety groups say the same thing in plain language. The NFPA Security Bar Safety sheet warns that some security bars can trap you in a fire and can keep firefighters from getting in to rescue you. It says to find at least two ways out of every room, make sure every exit, including barred windows, opens easily from inside, choose bars with quick-release devices, and hold a home fire drill twice a year.

That means no key, padlock or tool on bars over a bedroom or basement escape window. Ever. Read more in our window bars and fire code overview.

Start with what each room is used for, not with the bars. The table is a decision aid based on the 2021 IRC sections above. It is not legal advice, and local code may differ.

If the basement opening sits below grade, R310.4 calls for an area well. R310.4.1 sets the well at no less than 9 square feet with at least 36 inches in each direction, and R310.4.2 requires a permanent ladder or steps if the well is deeper than 44 inches. Bars must not block that route. Our guide to basement window bars goes deeper.

One limit matters more than any table. Security bars are not child fall protection. Bar spacing does not contain small children or pets. The NFPA sheet says a window guard, a gate, or a window stop or wedge can keep a child from falling out of an open window. If that is your concern, solve it with those devices instead.

SWB sells three telescopic models. Here is what each one is, taken from the product pages as of 31-Oct-2026.

The Model A costs $85 per core module. It telescopes from 35 to 65 inches high. Width is modular at 16 inches per module, so you stack modules for wider windows. Bar spacing is 5.25 inches. It is galvanized steel with electrostatic paint and mounts to the frame or the wall. It has no integrated quick-release, so it suits windows that are not escape openings. Installation takes 15 to 30 minutes. The manual has you drill pilot holes and use the included anchors, so it is not a no-drilling product. It carries a 1-year limited warranty.

The Model B also costs $85 per core module and covers 35 to 61 inches in height. It is a wall-mount option for masonry, stucco and irregular frames. SWB lists it as not rated for fire code or egress, so it belongs only on windows that are not escape openings.

The Model A/EXIT is quote only and sold online exclusively. It has a 35-inch base that telescopes to 65 inches high, and a 43-inch base width that expands with modules. SWB describes it as its egress-compliant model and the only one with a built-in quick-release: a hand-operated lift-bolt release from inside, rigid from outside. Whether the installed window complies is the building official's call, not the manufacturer's.

In short, pick by window, not by price. A bedroom or basement escape window points to a quick-release model and a call to your building department. A window that nobody needs for escape opens up the other two.

Work through this list before you order. It takes less time than returning bars that do not fit.

• List every window you want to bar and mark which ones are bedroom or basement escape openings.
• Call your local building department and ask what applies to bars over those windows.
• If you rent, get written permission from your landlord first.
• Measure the opening height and width, and note the frame type: wood, vinyl, masonry or stucco.
• Choose a quick-release model for every escape window. Never add a key, padlock or tool-operated lock to it.
• Check that the bars leave the required clear opening and do not block an area well.
• Fit smoke alarms and test them.
• Run a home fire drill that includes the barred window, and repeat it twice a year.

On alarms, the NFPA Smoke Alarms at Home sheet says to put them in every bedroom, outside each sleeping area, and on every level including the basement. Test them monthly and replace them at 10 years.

For installation, read the manual first. Pilot holes and anchors mean you need to know what is behind the wall or frame, such as wood, brick or stucco. Our window bars installation guide explains what to check before you drill. If a step is unclear, stop and ask rather than guess. A loose mount defeats the purpose of the bars.