When should we stop using the crate

Question
Our German Shepherd is 18 months old, he is crated during the day when my wife and I are at work, and when we come home in the afternoon we take him out and spend the remainder of the day and night with him.  He receives exercise daily as my wife is a runner and takes him with her.  We are wondering when is the appropriate time to allow him the run of the house and no longer crate him.  We are concerned that he will tear up our home, and he does have a tenancy to get into things and occasionally chew on pillows, curtains, etc.. during the few occasions that we allowed him to be out of his crate in our absence.  Is the crate a permanent solution or should we already allow him to live in the house without a crate.  He has not been fixed, but is not overly aggressive (except when someone comes to the door). Your help is greatly appreciated, thanks.

Answer
I would never take the crate away completely, at least leaving it around with the door open.  Since he has proven untrustworthy, I would continue closing him in it for another year at least.  I have had few problems with the young Labs we have had recently allowing them loose when I was outside or in the garage.  However, many of the ones we have had before couldn't be left loose unsupervised.  Another factor is the crate restricts activity allowing the dog to go longer without relieving itself. Our one Lab will be 14 next month.  When we aren't around, we still leave her on a tie down as her partner did while she was still working as a dog guide.  

If you really want to make things better for him, you could leave him at a doggy day care.  He could spend the whole day in supervised play with other dogs.