Hi,

Referring the guide, equation 2 allows the use of SR / SRI weighted ratio to calculate the required area.  I do not quite understand the logic of this equation. 

To simplify the disucssion, if we assume there are no "Area of other nonroof measures" and "Area of vegetated roof", this leaves us with SR nonroof pavers and SRI roof pavers.  So if I am not mistaken, IF all nonroof pavers achieve an SR value of 50% of the required initial SR value (say 50% of SR 0.33) and all roof pavers achieve an SRI value of 75% of the requred initial SRI value (say 75% of SRI 82), based on the equation, the project will still jusst meet the crietia greater than or equalt to site paving area + roof area, whilst in fact, none of the selected pavings meet any of the initial SR / SRI criteria.

The above does not seem logical.  Any advice if my interpretation is correct or not.

Thanks