Egress Windows Code

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Egress Windows Code, Requirements And Building Codes

Let's explore egress windows code, requirements and building codes that specify number of exits, window width and height, distance from the ground and more. Of course, codes and requirements will differ from state to state and county and county. That's one of the reasons why it's so important to contact a professional egress window company or to refer to the building codes in your city or county for the proper basement requirements.

Below, you will find the summation for lots of egress window size requirements. Specifically, these includes things like the locking mechanism, window well requirements, net clear opening, etc. Additionally, we have listed several state requirements.

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California Egress Windows Code

Number Of Basement Egress

Basements that are used as living spaces are required by law to have at least one emergency escape route. This can either be a window or door. These emergency exits are called both a basement egress or simply an egress exit. If the basement is not being used as a living space, workout room, laundry, game room, etc., then homeowners do not need to install an egress window. And can save themselves some significant money.

Locking Mechanisms

An egress window or door must be able to be opened from the inside without having to use a key, crank or other tool. There cannot be objects that are blocking an individual from easily being able to open the window.

Egress Windows Code: Window Well

The exterior window well must be large enough for the window to open completely. The window well needs to have horizontal dimensions of at least 9 square feet and at least 36" of horizontal projection out from the house.

Ladders And Steps

If the window well height is more than 44 inches, then there has to be a permanent ladder (or integrated steps) attached to the window well. The inside of the ladder rungs needs to be at least 12 inches wide.

Window Distance From The Ground

The bottom window sill should be no higher than 42 inches (44 inches in some counties and states) from the finished floor. This placement is low enough to the ground to allow a child to crawl out of the egress window.

Egress Net Clear Opening

When the egress window is opened, it must provide 5.7 square feet of net clear opening. This provides enough space for an adult or child to enter or exit. It also provides enough room for a firefighter to enter with their gear and equipment in case of a fire. This requirement goes down to 5.0 square feet if the window is at grade level. Below you will see the minimum egress window size for each type of window, although none of these minimums provides the required 5.7 square feet of net clear opening so the windows will have to be larger than these minimums in each case.

Casement Code Requirements

Casements must meet the following minimum window sizes for code - 20" wide & 24" tall. However, this minimum sized window does not provide the required 5.7 square feet of net clear opening. Therefore, the window you buy and install must be larger than this minimum.

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Slider Egress Windows Code

Sliders must meet the following minimum window sizes for code - 4' wide & 4' tall. However, this minimum sized window does not provide the required 5.7 square feet of net clear opening. Therefore, the window you buy and install must be larger than this minimum.

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Double Hung Code Requirements

Double hungs must meet the following minimum window sizes for code - 3' wide & 5' tall. However, this minimum sized window does not provide the required 5.7 square feet of net clear opening. Therefore, the window you buy and install must be larger than this minimum.

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Single Hung Code Requirements

Single hungs must meet the following minimum window sizes for code - 3' wide & 5' tall. However, this minimum sized window does not provide the required 5.7 square feet of net clear opening. Therefore, the window you buy and install must be larger than this minimum.

More On Single Hungs

California Egress Windows Code

In California, egress windows are governed primarily by the California Building Code (CBC), which is based on the International Residential Code (IRC) with state-specific amendments. These windows are critical for safety, providing a means of emergency escape and rescue, particularly from bedrooms and below-grade habitable spaces like basements.

According to the CBC, every sleeping room must have at least one operable emergency escape and rescue opening. This requirement ensures occupants can exit safely during emergencies such as fires. The opening must lead directly to a public way, yard, or court.

The minimum size requirements for an egress window in California are as follows: minimum net clear opening: 5.7 square feet (5.0 square feet for ground-floor windows), opening height minimum: 24 inches, minimum opening width: 20 inches, and maximum sill height: 44 inches (above floor).

It’s important to note that these dimensions refer to the actual openable area, not just the window size. Window wells are also regulated. If the bottom of the window opening is below ground level, a window well must be installed with a minimum horizontal area of 9 square feet and a minimum dimension of 36 inches in width and length. If the well is deeper than 44 inches, a permanently affixed ladder or steps must be included.

Additionally, any security bars or grilles installed must be releasable or removable from the inside without tools or keys, ensuring quick egress. Local jurisdictions may impose additional requirements, so always consult local codes or a building official before beginning construction or renovation.

Ohio Egress Windows Code

The following information is based on the Ohio Residential Code (IRC). The minimum size requirements for an egress window in Ohio are as follows: minimum net clear opening: 5.7 square feet (5.0 square feet for ground-level windows), opening height minimum: 24 inches, minimum opening width: 20 inches, and maximum sill height: 44 inches (above floor). Additionally, the window has to be operable without the use of keys, tools, or significant effort.

However, if the window sill is below the exterior grade, then the window well must be at least 3 ft by 3 ft (9 ft² total area). And window wells that are deeper than 44 inches require an attached ladder or built in steps. Additionally, the well must be big enough that the window can fully open. Finally, any well cover must be removable without the use of tools.

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