Cottage Q&A
QUESTIONWe drain the plumbing at our cottage every fall, but get up there a couple of times during winter. When we use the toilet, which is china, we make sure to fill the bowl with plumbing antifreeze; the tank is always empty and dry. Last February, we visited for three days - outside temperature was -30°C - and followed the usual procedure. When we went back a month later, the tank of the toilet had cracked from side to side, though the bowl was fine. Why?
ANSWER
Strange indeed - considering we've just been telling readers that none of the materials used in bathroom fittings are susceptible to cracking in the cold! We asked John Etienne whether this tank could have cracked, as he described, because the walls had shifted from frost heaving. "Not in this case," he told us. "If anything, the bowl would crack, because it's the bowl that's fixed to the building, not the tank." Instead, Etienne thinks there must have been a manufacturing flaw in your tank.
Dennis Atchison, of Crane Plumbing Corp., agrees this is a possibility. In casting vitreous china, the occasional bubble can be trapped, he explains. If a water-filled bubble freezes during temperatures as extreme as those of last February, it could expand enough to crack the tank. It can also be tricky, Atchison says, to completely drain all the bits and pieces of the mechanism that empties and fills the tank. It's possible that, though the tank looked dry and empty, there was enough water left in the valve assembly to freeze, and damage it.
* Published in the November/December 2003 issue of Cottage Life
