Old House Rule

Here's an old house rule I used years back but seem to have stopped using in recent years for no good reason.

The Risk of Breaking Down Doors, Bending Bars, and Other Feats of Strength

 PCs can try again an again to break open doors, bend bars, or other related fits of strength but not with impunity. The first roll has no risk, the second and further tries by an individual are  risky becasue there's a 1 in 6 (non-cumulative) chance of suffering a hernia which limits one to half speed and -2 to hit rolls and saves that require moving, it takes 3 days of travel free rest to recover from this condition. 
If three attempts have already been made on a specific feat of strenght for the day and it's still your first turn you run the risk of attempting what others have failed at, but you do get a save to avoid the hernia on your 1st try (if 3 other previous rolls failed).