Hello, I just moved into a brand new condo and last night I turned on the master bath sink's hot water and let it run to heat up. I left the room for a minute and when I returned there was a large crack around drain and running up the back side of sink. Crack goes all the way through sink in some place because a small amount of water leaked through.

I understand the possibility of kitchenware cracking with extreme temp changes but the sink wasn't particularly cold (it is 73 degrees in house) prior to the hot water and should have warmed a bit as water from tap warmed.

My main question is: Is this normal for a porcelain sink or does this suggest the presence of small defect in the sink prior to the hot water?

Not sure if it matters but the sink is a standard size oval undermount sink mounted to a granite counter.

Thank you for help.


Quick correction: Not sure porcelain is the correct material description. Vitreous china maybe?

You're the first! Got to be a flaw in the casting. China lavatories don't develop cracks behind a little hot water. You should get a replacement at no cost to you.
Good luck, Tom

Could be;

A. Defective sink,
B. Fasteners securing sink to granite to over torque.
C. Rabbit or recess cut into underside of granite top cut to small, allowing no room for expansion.

All good poinrs Harold. I wondered about the clips under the lavatory being too tight and the lav expanding under the run of hot water and cracking. You've given Williarp some good answers. We may never know the real reason but you helped take the mystery out of it. Tom