### Problem
>We are putting this pattern in the language because our experiments have shown us that lay people often make mistakes about the volume which a staircase needs and therefore make their plans unbuildable.

### Solution
>Make a two story volume to contain the stairs. It may be straight, L-shapes, U-shapes, or C-shapes. The stair may be 2 feet wide (for a very steep stair) or 5 feet wide for a generous shallow stair. But, in all cases, the entire stairwell must form one complete structural bay, two stories high.
>Do not assume that all stairs have to have the “standard” angle of 30 degrees. The steepest stair may almost be a ladder. The most generous stair can be as shallow as a ramp and quite wide. As you work out the exact slope of your stair, bear in mind the relationship: riser + tread = 17 1/2 inches.

### Related Patterns
... [[Staircase as a Stage (133)]] and [[Open Stairs (158)]] will tell you roughly where to place the various stairs, both indoors and outdoors. This pattern gives each stair exact dimensions and treats it like a room so that it becomes realistic in the plan.

Construct the staircase as a vault, within a space defined by columns, just like every other room - [[Columns at the Corners (212)]], [[Stair Vault (228)]]. And make the most of the staircase; underneath it is a place where the children can play and hide - [[Child Caves (203)]]; and it is a place to sit and talk - [[Stair Seats (125)]] ...

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> [!cite]- Alexander, Christopher. _A Pattern Language: Towns, Buildings, Construction_. Oxford University Press, 1977, p. 900.
> #APL/confidence/medium
>
> #APL/Building-Patterns/Shaping-the-Rooms