Whats that they say about great minds thinking alike? I have just sent the violations forum a pic of this exact violation!
Your problems with using a 'standard box' are numerous. You've already identified the problem of someone breaking the coverplate.
You are also not able to adjust the heigth of the box, to acount for the finished floor.
The box itself is only supported on one side. And-
An unused receptacle is fully exposed to water and falling debris.
Ironically, it is the flush mounting of the box that makes this different from, say, mounting plugmold on the floor. I suppose that, were the receptacle mounted in a place that you could be confident it would never be stepped on (like under an altar), you might be able to get away with it. Otherwise- forget it- use the right box!
I priced on made by Carlon at the parts house, and I think it cost $10....quite affordable!)
