About This Calculator
This calculator estimates the amount of joint compound (mud) and tape needed to finish drywall joints and screw heads. Standard practice requires three coats: a bedding coat, a fill coat, and a finishing coat.
Finishing Process
- Apply bedding compound and embed paper tape into joints
- Apply second coat, widening the feathered edge
- Apply final skim coat and sand smooth once dry
- Fill all screw/nail heads with compound (3 coats)
Tips
- • Use paper tape for most joints; mesh tape for repairs
- • Allow each coat to dry fully before the next (typically 24 hours)
- • Feather edges wider on each successive coat for a smooth finish
- • Add 10% wastage for mixing losses and corrections
Ready to Calculate?
Enter the number of drywall sheets and screw pops to get compound and tape quantities.
Open CalculatorRelated Calculators
TXTexas IBC / IRC (AHJ amendments)
References & Sources
Standards Cited
- ASTM C475 — Standard Specification for Joint Compound and Joint Tape for Finishing Gypsum Board
Defines joint compound types and performance requirements for drywall finishing - GA-214 — Gypsum Association — Recommended Levels of Gypsum Board Finish
Specifies finish levels (0-5) and corresponding compound application requirements
Formulas Used
- Joint length per sheet:
jointLength = sheetWidth + sheetHeight (accounting for shared edges)
Source: GA-214 — Approximation: ~3.4m per standard NA sheet (4x8 ft / 1219x2438mm) - Compound volume:
compound = (jointLength × jointWidth) / coveragePerLitre × numberOfCoats
Source: Manufacturer coverage data — Joint feathering width ~125mm (5 inches) - Screw pop compound:
screwCompound = numberOfPops × 0.005 litres × numberOfCoats
Source: Industry practice
Key Assumptions
- Joint compound coverage ~1.5 m2 per litre per coat (USG all-purpose) — Manufacturer data (USG, National Gypsum)
- Standard tape roll: 250 ft (76.2 m) — USG / manufacturer standard
- Standard drywall sheet: 4 ft x 8 ft (1219 x 2438 mm) — ASTM C1396