The cost for board footage is calculated by dividing the total cost by the total board footage and then adding a waste allowance percentage to account for material loss during processing.

The formula for calculating the cost for board footage is given by:

\[ \text{Cost per Board Footage} = \left( \frac{\text{Total Cost}}{\text{Total Board Footage}} \right) \times \left( 1 + \frac{\text{Waste Allowance}}{100} \right) \]

where:

- \( \text{Total Cost} \) is the total cost in dollars
- \( \text{Total Board Footage} \) is the total board footage in board feet (bf)
- \( \text{Waste Allowance} \) is the waste allowance percentage

Let's assume the following values:

- Total Cost: $1000
- Total Board Footage: 500 bf
- Waste Allowance: 10%

Using the formula:

\[ \text{Cost per Board Footage} = \left( \frac{1000}{500} \right) \times \left( 1 + \frac{10}{100} \right) \]

Calculating step-by-step:

\[ \frac{1000}{500} = 2 \]

\[ 1 + \frac{10}{100} = 1.1 \]

\[ \text{Cost per Board Footage} = 2 \times 1.1 = 2.2 \]

The calculated cost per board footage (including waste allowance) is $2.20 per bf.