The last couple of weeks I have noticed a stale urine smell in my washroom. I scrubbed the washroom top-to-bottom, but the smell persists :(
Today I noticed that the grout at the "corners" of my toilet appears to be a little damp (photos below). Could this indicate a leak with the wax seal, and be the cause of odor?
If so, I guess the solution is replacing the wax seal, drying out the area underneath, and (depending on damage) replacing drywall ceiling underneath (it's a second floor washroom)?
There are numerous explanations for possible causes of moist grout near your toilet base, one of them being a compromised wax ring.
Some modern wax rings have an integral plastic funnel that allows gravity to direct water/waste into the drain line, which helps prevent leaks (under normal circumstances) even if the wax is compromised. I would recommend that you carefully examine the unit for other signs and if you find none go ahead and pull the toilet. Get a friend to help, they are unwieldy, and use a ring like I mentioned above when you replace it.
First check for leaks. Especially the feeder pipe joints and where the feeder enters the tank. Also check where the tank sits on top of the bowl. Puddles that are continually forming are most often sourced here. Also check the porcelain for hairline cracks.
Water on the outside of the toilet can also happen in a high humidity environment. If the humidity is high enough, and your toilet water cold enough, water will condense on the outside of the toilet bowl and tank and ultimately dribbles down onto the floor. This is often referred to as sweating. And yes, it can form quite the river on the floor before you notice it when your sock gets wet when you go pee...
It is not always as obvious as the picture above though. Run your finger over the outside of the porcelain and on the feed pipes, or use a bit of toilet paper. If it comes out wet.. your toidy is sweating.
This is usually a temporary phenomenon and only occurs on very humid days when the dew-point is in a specific range.
There are a few fixes for this,
One is insulating the tank to keep the coldness of the water away from the humid air around it. Most new tanks already include an insulated lining.
A more active solution is to install a small bore hot water feed that gets added to the cold water as it fills the tank. However, unless this is a continual problem I don't recommend this one since most of the year you will just be wasting hot water.
Neither solution stops water from condensing on the bowl if it sits a long time.
For my region, this only happens a few days a year, and when it does I simply drape and tuck in a white towel over the tank. It's not exactly pretty, but it's not awful, and looks better than having the towel lay on the floor to soak up the drippings. Some folks do use a toilet "caddy". A tailored and usually decorated toilet cover.
As for the bowl itself. Institute a house rule on humid days... As the old adage says.. "If it's brown, flush it down. If it's yellow, let it mellow." Try not to flush the toilet more often than you absolutely need to. Every time you flush it the whole system is filled with cold water, let it sit and acclimatize as long as you can.
A leak under the bowl is also possible of course, but is usually the least likely. Water leaking here will also, usually, NOT be clear and will have a not so delicate aroma.
PS: If you find a leak between the tank and the bowl.. DO NOT OVERTIGHTEN the bolts. Over-tightening can and will break the tank entirely. It's meant to be a soft compression joint.
