Bedrooms require a secondary meas of escape and rescue—usually it is a window. Most people take this to mean that there has to be a second way out of the room—but just as important it is a way for emergency personnel to get into the room.

Teenagers will often have their own reasons.
Size requirements necessary to meet current standards are sometimes confusing and difficult to understand. This post will attempt to inform the reader as to these requirements.
The minimum “clear opening” width is 20” and the minimum “clear opening” height is 24.” I would be pretty simple if this was all we had to know about it, but these dimensions do not take into account that there is also a minimum “sq ft” requirement. 5.7 sq ft when the window is NOT a grade and 5 sq ft when it is at IS at grade.
“Clear Opening” definition. This means that the measurement is made from anything that protrudes into the opening—such as the sash of the casement window pictured at the left—not the width of the opening if the sash were not there.
“At grade” is defined as not more than 44″ above the ground/landing when measured on the exterior side.
With a little simple math we would find that a window 20″ x 24″ would only have 3.33 sq ft and therefore would not meet escape and rescue opening requirements.
The diagram below shows that if a window has a clear opening size of 20” wide, we would need a height of 41.05.” Any rectangle, the sides of which fit against the two purple lines, would have to have the opposite two side’s corner intersect the diagonal blue line if the window is above grade. If the window is at grade, we can use the green line.

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Nice diagram, I wonder what is the requirements for a egress window for the basement in NJ.
It all depends on what codes they follow in your jurisdiction. This diagram works for most jurisdictions that have adopted the IRC codes
What are the egress requirements for a 2nd story bedroom window? We’d be heading out to a very steep roof from the window.
Thanks,
Susan
Susan, the actual size will vary. The minimum width is typically 20 inches with a minimum height of 24″ but the total square feet has a minimum of 5.7 square feet. Lets say for example the window net opening is 20 inches, then the minimum height would be 41 inches.
are there any requrments on how far off the ground the window needs to be on the interior side. this specifically matters for basement windows where they would be “at grade externally but not at grade internally
44″ above the floor, regardless of where the window is.
Nice Blog! Thanks for putting useful info out there.
Just to be clear, when a bedroom has two doors (several feet apart, on different walls), then the requirement for secondary egress is met even without windows? (I live in Renton).
Dave, one of those doors would have to be to the exterior of the home.
So I can put a single hung window 36×48, 44 inches above ground in the basement?
Well it might be more complicated than that. It is the size of the area that opens that is critical, as well as where it opens to. You would have to consult with your jurisdiction for the best answer to this.
What are the egress requirements for a third floor attic bedroom with an interior stairway and a window that opens but is on the third story elevation with no roof surface so exit is a three story jump?
Pretty much Jay. But keep in mind, these egress requirements are for firemen as well and the higher they are off the ground the more important the proper size windows are. It may not be ideal, but it is better than nothing. Non single family residential would likely require fire escapes and other solutions.
can i use a casement window as an egress? exterior is at grade
Sure, as long as it meets the net opening size requirements
thank you very much
Do you have any contractor recommendations for someone who could cut concrete, dig some more, and install a new window to create a proper, to code, window egress in a basement bedroom in West Seattle?
If the basement window is higher than 44″ from the floor, would it meet the code if a ladder gets permanently attached to the wall?
If the answer is no, is there no way other than to cut into the cement and create a basement window well?
You would have to ask your jurisdiction that question, but I doubt a ladder is going to fly. A permanent floor/platform would work if you have room maybe.
are you sure the net opening width and square feet requirement are met with that window?
Thank you for your kind and prompt reply Charles.
Windows will need to be replaced to meet the net opening.
If a permanent floor/platform is not acceptable, would cutting into the cement and creating a basement window well be the only option here?
Most likely.