What!! Puppies need company - they need to interact with their humans. You cannot just dump them in a pen outside and never walk them out, never play with them, never train them ... and expect them to then urinate and defecate on command outside the pen, and then shove them back again.

Well said! How the OP thinks that when he brings the poor little guy into the house he is suddenly and miraculously going to be house-trained I dread to think! He has had no training it would appear, little or no exercise, and will have no idea how to behave in a human household.

Thanks for asking and give me the opportunity to clarify all these things Chris.
While rushing to post these questions i really didn't make myself clear and i don't blame on anybody for being so angry.
Seriously.. im with you all.
'Based on my quick comments i really look like a monster and although it's not about me I just would like to let everybody know that i would never adopt a pet to ''re-lock/isolate'' him again.
I'm a spiritual person ( well... on the path i believe ) and I'm very connected to nature and animals in general. I don't even kill a bug or a centipedes because i truly understand it's nature and i think it's part of me somehow. ( This is not just a expression or way of saying things. I really don't! ) Leave alone treating a dog that bad....
The reason i have setup my boy's playpen in the garage is because it has more space for him/us to play and do lots of things together. My garage is not an abandoned junk yard.. I'm there most of the time working out in my home gym and etc etc..Also, my backyard is just one door away and i take him outside all the time...And Yes, i take him inside too ! All the family interacts with him a lot. If we leave the house for some reason other than work. He's right there taking a ride.
So.... the reason i asked what could be done in order for him to understand that he has plenty of space in his pen to do some business in case something happens is simply because.. things happen ! And because i care, im desperately trying to look for quick solutions. What if something happens and i can get home? What if nobody else can do it on my behalf ? ( A dog walker for instance ) I just don't want the little guy experiencing such a horrible situation and i see gazillion dogs setting aside some room in their playpens to use as a bathroom.I think it's more than natural for me to expect the same thing to happen. I said expect. Not to force it !!
I'm not expecting him to behave like a adult human inside the house. This is not my point. In fact he actually goes on a pad when he's inside. That's a bonus right there i guess...
I think that's it. Thank you all for your comments

Hi. I may be wrong, but reading between the lines, your pup is rarely left for long periods in his playpen? It seems from all your posts that usually either you, your wife or son is at home for the largest chunk of the day.

I do think that you may be storing up a problem though as you say that you will move your pup indoors with you when the weather turns colder. If he isn't used to the house at that point, you will have to start over again from the beginning with him as he will be in a relatively new environment. Far easier to spend more time indoors with him now to habituate him to life indoors.

Dogs are far more adaptive than we give them credit for, however. As he gets older, he will be able to safely hold his bladder and bowel movements for longer periods so your concerns now will not apply

Sorry, but I am at a loss as to why you would want your dog to give up and "do this thing" in the house - let alone in an area which he obviously regards as his bedroom.
Sorry, but 8 hours is far too long to leave a young puppy on his own - I hear of this so many times and it is not fair to expect your pup to "do its own thing" for the best part of the daylight hours. Your pup also needs to have company and to be taught - they grow so quickly and need to learn. IMO what you are doing is confining your puppy to a prison - in fact it is a prison sentence.
Sorry, but I feel this so strongly and I wish people wouldn't think it is OK to do this to a live animal. The best solution for you would be to get a stuffed toy and re-home your dog to someone who really cares about its welfare.

You got it Chris. He's not alone and ''shoved'' in his pen most of the time and i'm not waiting to bring him inside some day. He is already inside everyday and all the training that you recommend is been done since day 1. The only reason i asked what i asked on my original post is because the idea of coming home late for whatever reason scares me to death...

Hello there,

If you read my previous post above you'll notice that the reality of my puppy is not what you thinking. I was just asking if something could be done in order for me to teach him to use a pad inside his playpen in case i get home late ( for whatever reason )without him going through all the stress of holding it for too long...