I have a 10-year-old house and have recently begun noticing that there is water leaking through the floor in the bathroom in three distinct spots. The grout between the tiles seams to be in pretty good shape and I recently sealed it. I also re-caulked around the tub. The water appears to be coming from the back of the tub just before the wall joist and some is even leaking under it to the bedroom next to it. Do you have any idea where it could possibly be coming from?
There are many places that water could be coming from when a leak or water stains are seen in the vicinity of a bathroom. They may be related to the shower in question, but this may also be a “red herring”. Without seeing the damage, it is tough to find the cause of this common problem, but I will offer up a few possibilities.
Something that wasn’t mentioned was whether the bathtub has a shower and what type of enclosure is present. I will assume that there is a shower and either a curtain or door style enclosure. This is the first place to look and is the likely culprit. One of the most common problems seen in bathroom inspections is damage to the walls adjacent to tubs. This is usually found just below the top of the tub where the wall covering butts up against the tub. The cause is normally leaking from behind the curtain or at the edge of the shower doors.
If a curtain is present, a small plastic dam can be installed at a diagonal angle near the rear and front of the tub to redirect the water back inside when showering. These simple and inexpensive devices can be bought at most home centres or department stores. They are usually glued in place with silicone caulking and can be quite effective.
When shower doors are installed, they are normally screwed in to the wall and sealed at any joints with silicone. This silicone wears, with time, and has to be removed and re-caulked. Two places many people neglect to caulk are inside the bottom door track and along the shower side of the wall tracks. The respondent mentioned that he had caulked around the tub, but this may be the offending area if not included.
Hopefully, a little silicone caulking and elbow grease will solve this problem. Other alternative causes may be more serious and costly. It is not common for tiled shower walls to leak without visible grout damage or loose tiles. Sealing the tile grout will not do much toward waterproofing, but will ease cleaning. If the grout is cracked or falling out, then it should be removed and the walls re-grouted. This is an inexpensive job that most homeowners can do themselves, but is quite labour intensive. If any tiles are loose, they must be removed and the drywall or wall sheathing behind replaced. This can be a very expensive and messy job if all the tiles and sheathing have to be replaced.
Other possible causes of water damage may be leaking plumbing supply lines, drains, or fixtures. Excess condensation may also be a possibility if the house is in an area of very high humidity. Check all visible pipes for sweating and dripping. If a toilet is near the wall in question, the problem may be as simple as a leaking wax ring at the base of the toilet.
Most of these other defects are harder to detect and often require dismantling of cabinetry or wall and floor sheathing. If caulking and grouting the shower area doesn’t improve the situation, it will be time to call in a licensed plumber to get to the bottom of the situation and correct it. Whatever the source of the moisture, procrastination will only lead to expensive and intrusive repairs. Whether it is a toilet, sink, or shower causing the problem it’s time to “poop or get off the pot” and find the problem, as it will only get worse with time.