Changes to standards governing step downs

We are in the process of working out how to do our patio and have found that in order to stay 75mm below the weep holes on my son's bedroom wall, the patio to the living area will have to have a 140mm step down from the house. In trying to find out whether this is an allowable step down according to the BCA, I came across some information which seems to suggest that the Australian standard for waterproofing decks and balconies has now been changed to 100mm (or you need to install a grate). See attached link: http://www.infotile.com/pdfFile/advicet ... 031328.pdf

I don't know whether I am understanding this correctly or not. Does somebody know whether this is, in fact, the case? And can somebody tell me whether 140 mm is an acceptable step down height from the house? (Actually our step down from the front door to the front porch deck is 180mm!) It just doesn't seem very old-people friendly and I don't know how to get around this height problem.

Liliana, the 75mm clearance from the base of the weep holes to a finished surface level (sloping away from the slab edge) would be the minimum base figure to work from. The maximum rise of a step is 190mm & the minimum 115mm.
Hope this answers your question.

Thanks Ausdesign. That does answer my question. That's grand.