The stair landing in this picture is built out 2 x 6 with 4 x 8
structural supports. This is a common
stair landing that sits on
top of one wall and is fastened to the outer walls creating a landing
The small arrow on the left point to the upper section of a two step (or part) landing. Due to the number of steps required and limited space, the architect chose to put a step in the landing. If they didn't put a step in the landing they would have needed to add an additional step at the top or bottom of the stairway.
Tip there are many designs and shapes to use for your stair landing, if you have limited space in your building you will have other options and methods available to you.
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