Corner bead protects every outside corner where drywall turns a corner. Most takeoffs count it around door and window openings: two jambs and a head. A wall that simply stops in the room (a pony wall, a stub partition) has an outside corner too, and it is easy to leave out.
The count
A free end is one full-height run of bead for each drywalled face.
- A 16 ft partition, 8 ft high, drywalled both sides, with one free end: 1 end x 2 faces x 8 ft = 16 ft of bead.
- The same partition with both ends free: 32 ft.
- An exterior wall drywalled on its inside face only, one free end: 8 ft.
At 8 ft sticks with 10% waste, 16 ft is 3 sticks (16 x 1.1 / 8 = 2.2, rounded up).
In the tool
The free wall-framing takeoff now reads a freeEnds value (0, 1 or 2) on each wall and adds these runs to the bead count it already makes for openings. The plan states which ends are free; the tool does not guess from geometry. The three counts above are tests in drywall.test.mjs.
Not covered yet: bead on ceiling steps, trim, and a page field for freeEnds (it is set in the plan JSON today). Bead is a rule of thumb for what to order; check the layout against your drawings and local practice.