Doing some reading I have seen the requirements for various sized headers over windows depending on the span. While thinking about this, I ran down to my basement (house built in the 20s) and confirmed that the basement casement windows had no header but the bottom of the sill was at the top of the windows. Is this typical in modern construction? Is the lack of header due to the fact that the window is in concrete? If this is present construction, is it becuase the window span is about 32″ or can longer windows be placed in the foundation without headers?
The basement is a full basementwith concrete walls.
Thanks for any information