Advice needed on holding potty

Question:
 Not sure if the heading made sense, but I need some advice. Major, my 17 week old puppy, is left home alone from noon until about 5:30 during the week. He stays in our bathroom, which is rather large, room to play around in. My question is does anyone have any tips on how to entice the dog to hold his pee longer until I can get home to let him out?
Before answering, please know that this was not the situation I planned to be in when I got the dog, and I am actively working to change my schedule to allow me to come home earlier as well as in between that time to let him out. However, I do know that he can hold it, because I have come home a couple of times when he has, and the other day I got off work an hour early and raced home to see that he had held it and he instantly ran outside and peed for hours (well a few minutes anyways). So I'm thinking it's that last hour that gets him. I've just assumed all this time that as he gets older he will hold it long enough, in which I will then give him free roam of the house eventually, and until then keep cleaning it up when I get home. I hadn't punished or really rewarded any behaviors, besides praise, because I know dogs live in the moment. Any suggestions?
Thanks so much!

Answer:
 Have you considered a crate. Dogs usually won't go where they sleep. Also at about 7-9 months they start getting into trouble & almost everything they learned has to be reinforced again. So he may start chewing your vanity or door frames, etc.
IMO a crate would help.

Answer:
 He is crate trained, and has no problem being in his crate. I just feel like leaving him in that little area for that long isn't fair to him. I try to give him the most area that I can without him destroying everything, as you mentioned (which we've been pretty lucky about).

Answer:
 How about a responsible teenager who would be willing to let him out after school? My son (15) has taken care of neighbors' dogs before.

Answer:
 I temporarily had the same issue with my pup when he was young. I think the crate is the solution if you don't have someone to take him out. I remember reading that for a young dog it was fine to leave him in the crate for about 4 hours. You are talking about a little bit longer, but it should be OK.
My dog absolutely loves his crate now. I thought he would hate it from having to stay in it as a pup. If he gets nervous now he runs to get in his crate. I usually tell him to "kennel" right before I feed him. He goes running in there and I set his bowl where he can eat from the crate. He also realizes that if the crate is in the truck that he gets to go somewhere. He is constantly jumping into the crate when it's in the car, even if the door is closed.
Point being, you need to work with him over the next several months and get him to love that crate. It's not as bad as we think it is sometimes...as long as it's not too long and he is getting adequate attention and exercise the rest of the time.

Answer:
 I'd do a crate too. 5 and a half hours doesn't seem that long really, not horrible.
Also you could limit water intake prior to leaving him that long, then he doens't have to deal with having to pee so badly?