4 feet
2756
a ladder or a flight of stair
Flight of stairs and Fleet of ships.
12-17
A flight of stairs in it's entirety is a staircase
The size of the board used for a stair stringer should typically be 2x12 inches.
Minimum tread is 10" and maximum riser is 7.75".
stair and stare
The minimum stair landing dimensions required for safety and compliance with building codes are typically 36 inches in the direction of travel and at least as wide as the stairs themselves.
The average stair size typically used in residential buildings is around 7 inches in height and 11 inches in depth.
For stair stringers, it is recommended to use 2x12 lumber for optimal strength and support.
Generally, a stair lift can be installed professionally for about $3500 for a standard lift, on a straight set of stairs and only a single flight. Turns and non-standard stair configuration will increase the price substantially.