Our building is historic, and in Canada. Flush fixtures (toilets and urinals) do not have any indication as to manufacturer, model, OR flush rate. For the purposes of our calculation we've assumed 3.5 GPM for toilets and 1.6 GPM for urinals. Our question is - where does LEED provide guidance as to appropriate measurement of flush rates? We implemented our own methodology, but I want to ensure it's acceptable. In the absence of any guidance in the reference guide or elsewhere, I assume that it is? Also, in lieu of sampling 20% of toilets to test their flush rate, is their a default value that LEED would find acceptable for old pre-1993 toilets? I'm surprised at how meager the reference guide is on this, but perhaps I'm overlooking something. Thanks for any information!