Unlike goats, sheep do not do well on an indoor regime. They need to roam and graze. They should also have companions of their own species.
If you do keep him on a dry diet, you will need to make sure he not only has access to plenty of fresh water but also that he drinks it. The urinary calculi are far more likely to form in a male sheep on a dry diet, whether or not it includes concentrates with or without any additives. Some people recommend salting the diet so that thirst is created, to stimulate drinking, but I'm not sure this would be effective in preventing calculi.
I'm guessing this tup's alternative is the chop, so I can see there is an argument that a non-ideal life may be better than no life. But for me, I would not feel right keeping a herd animal without company of its own kind, and I would not be happy keeping sheep without grazing year round.