There is not a clear and explicit approach for calculating how permeable paving contributes to SSc5.2. However, it is reasonable to count some of the permeable paving if it is an open grid system that is predominantly open-grid/vegetation. To calculate the permeable paving contribution, consider using a percentage of the total permeable paving area as vegetated—for example, if you have 1,000 ft2 of open grid, consider 500 ft2 as vegetation.