In answering your question, I would remind you, of course, that those aren't all PW buildings. That said, what transpires when a department runs into a funding pressure is that typically, to the degree that they can't allocate from within to cover it, a Treasury Board submission is looked at in the framework of all the competing government priorities. The government has to address the most urgent and the most pressing at the time.
On March 20th, 2007. See this statement in context.