Mechanical room covered by greenroof

By definition the mechanical room will be excluded from roof calculations. However, we are considering covering a mechanical room with a greenroof in order to apply for this credit. The issue here is that space is so limited and we need to provide 3300 sqft in order to comply with SSc7.2 and SSc5.1 as well. We ran out of space because, however if we covered a big mechanical room where hvac and elevators machinery are we will be able to comply with these two credits. But we dont want to run into a review saying the greenroof at the machinery room will be excluced from calculations. Does anybody have any experience of greenroof in machinery rooms being accepted in order to comply with credits regarding vegetated spaces?