Question re built up vs natural land ratio

For your typical NSW R2 residential zone suburban block - what's the max ratio of built up vs natural land? Not sure what the official terminology is but I'm referring to total area of buildings + structures where rain would hit a roof or driveway etc, as opposed to dirt/grass that absorbs rain - is there such a ratio? I know of a max FSR ratio which the council LEP maps define but is there also a max built up area ratio as I describe above? If so what's it called and where is the restrictions defined?

 

Site coverage?

 

I couldn't find anything substantial on 'site coverage' - mentions of it usually refer to FSR controls

Surely there's a control that would stop me from concreting the entire plot of land...

 

@scientist - controls are soft landscaping and storm water management.