How to use gross lumber from target yield
What this calculation does
A yield estimate works backward from usable output to gross input using the fraction of input expected to remain usable.
Enter the usable quantity you need and the expected yield percentage as a value greater than zero and at most 100.
Enter the measurements
- Net usable requirement: Enter the quantity that must remain usable.
- User-selected yield: Enter expected usable output as a percent of gross input.
Formula and variables
gross = net / (yield% / 100).
Gross input = net usable quantity÷(yield percent÷100). Yield is a divisor, not an overage multiplier.
Read the result
At 80% yield, 25 BF of gross input is needed to obtain 20 BF usable quantity.
Worked example
Inputs: 20 BF usable at 80% yield
- Yield fraction = 80÷100 = 0.8.
- Gross input = 20÷0.8 = 25 BF.
Expected result: 25 BF gross
Frequently asked questions
Can yield be entered as 0.8?
The input is a percentage, so enter 80 for an 80% yield.
Does it predict a species-specific recovery?
No. The yield value is supplied by the user and is not inferred from species or defects.
Conditions, presets and technical notes
Use matching measurement bases. Yield must be greater than 0% and no more than 100%; it is not a waste allowance.