Metal stud framing guide — calculating studs, tracks and drywall

Light-gauge steel (LGS) framing — metal studs and tracks — has largely replaced wood framing for interior partition walls in commercial buildings and is growing fast in residential construction. The calculation is simple but has one critical rule: always add an end stud. Skip it and your wall will not have a stud at the far corner.

Components of a metal stud partition

A light-gauge steel partition has four main components:

• Bottom track (runner): U-channel screwed to the floor. The studs slot into it. Length = wall length.
• Top track (runner): U-channel screwed to the ceiling or underside of the slab above. Same length as the bottom track.
• Studs: C-channel vertical members, floor to ceiling. Spaced at regular intervals and crimped or screwed to the top and bottom tracks.
• Drywall (sheetrock): Screwed to the stud flanges. One or both sides of the partition depending on the application.

Calculating stud count

Formula: Studs = ceil(wall length ÷ spacing) + 1

The ceil (ceiling) function means you always round up to the next whole number. The "+1" is the end stud at the far end of the wall — often forgotten, always necessary.

Wall length	16 in / 400 mm OC	24 in / 600 mm OC
3 m (10 ft)	ceil(3 ÷ 0.40) + 1 = 9	ceil(3 ÷ 0.60) + 1 = 7
5 m (16 ft)	ceil(5 ÷ 0.40) + 1 = 14	ceil(5 ÷ 0.60) + 1 = 10
8 m (26 ft)	ceil(8 ÷ 0.40) + 1 = 21	ceil(8 ÷ 0.60) + 1 = 15
10 m (33 ft)	ceil(10 ÷ 0.40) + 1 = 26	ceil(10 ÷ 0.60) + 1 = 18

Choosing stud spacing

• 400 mm / 16 in on center: Standard for 12.5 mm (½ in) drywall. Stiffer wall, better for mounting objects, superior sound isolation when insulation is added.
• 600 mm / 24 in on center: Acceptable for lightweight non-structural partitions with 15 mm (⅝ in) drywall. Fewer studs, lower material cost.
• 300 mm / 12 in OC: Heavy-duty applications — tile backing, high-traffic areas, or walls that will carry shelving systems.

Track calculation

Every wall needs two tracks: one at the floor and one at the ceiling. Track length = 2 × wall length. Both tracks are cut to exactly the same length. The studs then slot into both tracks — they do not attach at the ceiling track to allow for deflection in commercial buildings (a design feature called a "deflection track").

Drywall panel calculation

Wall area = length × height. Panels = ceil(wall area × 1.10 ÷ panel area). Standard panel size: 1.2 m × 2.4 m = 2.88 m² (4 ft × 8 ft = 32 sq ft). The 10% waste covers edge cuts, outlet cutouts and corner waste.

For a wall clad on both sides, calculate for one side and double the panel count.

Worked example — 5 m × 2.6 m wall, single face, 16 in OC

Item	Calculation	Result
Studs (16 in / 400 mm)	ceil(5 ÷ 0.40) + 1	14 studs
Track (top + bottom)	2 × 5	10 m (33 ft)
Wall area	5 × 2.6	13 m² (140 sq ft)
Area with 10% waste	13 × 1.10	14.3 m²
Drywall panels (1.2×2.4 m)	ceil(14.3 ÷ 2.88)	5 panels
Screws (28 per panel)	5 × 28	140 screws

Common mistakes

• Forgetting the end stud. The formula without "+1" leaves the far end of the wall without a stud — drywall cannot be fastened there.
• Not leaving a floor gap. Metal studs should have a 6–12 mm (¼–½ in) gap at the floor track to allow for deflection and to keep them off wet concrete. Deflection tracks at the ceiling serve the same purpose in commercial buildings.
• Using the wrong screws. Use Type S (sharp-point) drywall screws for steel framing — not wood screws. Incorrect screws spin without engaging.
• Calculating single-face on a double-face wall. A free-standing partition is clad on both sides. Double panels, screws and tape — not studs or track.

Use the free calculator

Enter your wall dimensions and stud spacing in the Metal Stud Calculator for an instant count. For the drywall-only quantities, use the Drywall Calculator.

Frequently asked questions