My boss showed me this along time ago - when he was angry with someone (whether justified or not) he would act as if they didn't exist. It would drive people crazy! We talked abut it one time and he said it was the most effective way (in his opinion) to punish and change behavior.
Boy was he right! My co-workers would lick the bottom of his shoes if that is what it took to get him to talk to them again.
IMO sometimes the silent treatment can be ones way of settling high emotion. If it continues beyond a couple of hours or so then its just a manipulation to get YOU to do something they want you to do.
Ignore him and continue status quo (speaking normally) even if he doesn't respond. At least things are peaceful in your house.