How to use
- Add the wall and ceiling surfaces that will actually receive joint finishing.
- Check the compound’s coverage guidance and adjust gallons per 1,000 sq ft.
- Use your tape coverage allowance and the length printed on the roll.
How the estimate is calculated
Compound gallons = surface area in square feet ÷ 1,000 × the compound allowance. Pails = gallons ÷ 4.5, rounded up. Tape length = surface area ÷ 1,000 × the tape allowance; dividing by roll length and rounding up gives rolls.
Example: 1,000 sq ft at 9 US gal and 375 ft of tape per 1,000 sq ft needs 9.00 US gal, 2 pails of 4.5 US gal, and 375.0 ft of tape. With 250 ft rolls, buy 2 rolls.
Compound type and finishing scope
| Planning input | Default | Source context |
|---|---|---|
| Compound | 9 US gal / 1,000 sq ft | USG FAQ summary: about two 4.5 gal pails of UltraLightweight All Purpose |
| Paper tape | 375 ft / 1,000 sq ft | ProForm paper tape listing summary |
| Pail size used for count | 4.5 US gal | The package size in the USG example |
These are product-related planning allowances, not universal application requirements. Ready-mixed drying compound and setting-type powder cannot be treated as equal package volumes. The pail result describes a 4.5 US gal ready-mixed package, not a count of powder bags. Follow the selected product instructions for mixing and application.
The tool does not multiply by a coat count. Enter an allowance for the entire finishing scope instead; additional coats, skim coating, and a different seam layout can change consumption. Tape use follows joints, so an area-based allowance is only an approximation.
Common mistakes
- Entering floor area instead of the drywall surfaces.
- Converting a powder bag’s weight directly into the pail count.
- Multiplying an all-finishing allowance by the coat count again.
Sources
USG joint compound FAQ and the ProForm paper tape listing were checked only as search summaries. The original pages were not read; defaults remain editable and are not official coverage guarantees.
Related calculators
Frequently asked questions
Does the compound rate mean per coat?
Use an allowance for the whole finishing job. The calculator applies it once and does not add another multiplier for coats.
Why does a small job still show a whole pail?
The gallon estimate can be fractional, but the shopping count rounds up to whole 4.5 US gal pails.
Can I use a 500 ft tape roll?
Yes. Enter the actual roll length, or its converted length in metric mode. The same tape requirement will then need fewer rolls.
Do the defaults cover a full skim coat?
No separate skim-coating allowance is built in. Get product guidance for that scope and replace the consumption rate.
Why do the rate fields keep US units in metric mode?
They retain the explicit per-1,000-sq-ft product allowance basis. Your measured area is converted internally before applying those rates.