You need to try and figure out why he is going potty in the house? Is he bored, does he really need to go outside (does he have access when you are gone), is he just going to go? Does he go in the same place each time, could he be marking his territory?

I am all for crate traning but I would try just giving him access to one room to start. If he continues to potty in the house then I would go with the crate training. Giving him access to only one room might also help you figure out why he is going in the house. Have you changed anything in the house? Laundry soap, carpet cleaner, new furnature, anything that might be new?

This is trainable but you have to know what causes it before you can stop it.
Good luck,
Gina