I'm buying a house and the sellers disclosed a leak in the CPVC pipe. The
water was off at the time of the inspection, but we could see the evidence.

The leak is in the hot water feed of the tub in the master bath. From the
basement, there is a small amount of staining on the plywood subfloor and
some efflorescence was evident on the concrete floor under the pipe. I
don't know how long the leak was there. From the bathroom, you can't see
the leak. The tub is framed in with no access panel.

I requested the pipe be repaired along with any damage resulting from the
leak. I was thinking that a plumber would have to cut an access panel to
fix the pipe, then he could see the floor from inside the tub surround. The
bathroom floor is ceramic tile, but it seems solid.

The sellers had a plumber come out, turned on the water, and said the pipe
wasn't leaking at that time. They've offered a $500 allowance for me to
make repairs after closing. Or they've offered a one year home warranty.

My question is, can a pipe stop leaking by itself? I wouldn't think so, but
I have limited experience plumbing. Also, is an examination of the floor
from the basement followed by bouncing on the tile upstairs sufficient to
guess about the integrity?

If I buy the house, the first thing I'm doing is cutting an access panel
next to the tub and looking for myself. But I would hate to get a huge
surprise.