Egress codes exist to provide emergency access to living areas of the home. These standards establish minimum requirements for windows used in bedrooms and basements with habitable space. At least one egress qualifying window or door is required in these rooms. If the room has a door to the outside, then this covers the requirements. If it doesn't, then at least one window must meet the code requirements.
Code requirements vary, depending on where you live. You must check with your local code officials to determine your specific requirements. There several code standards that are typically adopted, but the final authority exists with your local officials.
To help you select windows that potentially qualify, Sun has created an Egress ID system for our Casement and Double Hung windows. Please note that the window opening must be unobstructed, therefore Awning windows do not qualify. We base this on one of the typical, national standards, BOCA: The National Building Code. These standards happen to match many of the other code standards, but some do vary in some of the specifications.
Again, please check with your local code officials.
BOCA: The National Building Code, Chapter 10, Section 1010.4 (2006)
Maximum sill height above the floor = 44"
Minimum net clear opening width = 20"
Minimum net clear opening height = 24"
Minimum net clear opening square feet = 5.7
Exception - Grade level windows - minimum net clear opening square feet = 5.0