Laczko v. Alexander, 2012 ONCA 872 is a good source for the principle that, absent some other Rule, substaintial indemnity costs are to be awarded only in the rarest of cases:
 Laczko seeks costs on a substantial indemnity basis. The court's discretion to award costs is governed by s. 131 of the Courts of Justice Act, R.S.O. 1990, c. C.43, and by r. 57.01 of the Rules of Civil Procedure, R.R.O. 1990, Reg. 194. It is well established that costs should be awarded on a partial indemnity basis unless justice can only be done by complete or substantial indemnification: see Foulis v. Robinson (1978), 21 O.R. (2d) 769 (C.A.). As a general rule, justice will only require substantial indemnification where there has been "reprehensible, scandalous or outrageous conduct on the part of one of the parties": Young v. Young,  4 S.C.R. 3, at p. 134. Alexander's unjustified failure to comply with his disclosure obligations was no doubt worthy of rebuke; "reprehensible," "scandalous," or "outrageous," it was not. I would, therefore, decline to award costs on a substantial indemnity basis.