Advocate Master Plumbing has been helping lees summit plumbing customers with leaking ceiling diagnostics for years. A ceiling water leak can be scary. Water streaming from a light fixture or water stains on your ceiling can just make you see dollar signs. Finding the cause of the leak doesn’t have to cost you anything. Let us show you how our plumbers approach ceiling leak detection.
A plumbers diagnostic approach to a leaking ceiling
When I get a plumbing service call for a leaking ceiling I already know what it might be. There are a few very common reasons for leaks. And while taking the call I always have some questions for the customer. Then when I arrive I let them vent a bit and tell me their story. Even though this is routine for me, it’s a major life event for them. Once they’re more relaxed I can begin the leak detection process. It always begin with further questions.
Where is your ceiling leaking?
This is an obvious question. And usually I’m told during my customers retelling of the events. A brownish water mark on the ceiling is a small leak. But a larger leak will include a long straight brownish line. This is pooled water finding a seam in the drywall.
Is there a bathroom above the leaking ceiling?
It’s uncommon for pipes to leak. It’s usually a plumbing connection to the pipes. So I always ask if there’s a bathroom above the leak. A leaking tub or shower is most common. A leaking toilet is also very common. Then I try to go deeper with my questioning.
If I suspect a leaking tub I’ll first look at the caulking and grout around the tub. Caulking and grout are both temporary. They both need occasional maintenance or replacement. Shrinking caulk can actually channel water into the wall. And grout voids allow water to saturate backer board/drywall. The tile depends on this for structural integrity.
I’ll also check for a cracked tub or loose tub drain connection. And lastly, I’ll check for a loose overflow assembly or shower valve trim. This is usually easily repaired by either tightening a screw or sealing with silicone caulk. I’ll always use clear 100% silicone caulk. Clear because it’s easier to work with.
A shower leak will be checked the same as the tub leak. But I’ll also check the special shower drain. A cracked shower drain on the shower base is very common. The shower bases can sometimes flex when walked on. If the drains are made of plastic, the flange portion of the shower drain can crack or loosen. This will require a replacement. My preferred shower drain replacement is manufactured by Sioux Chief and is brass. This is a permanent repair.
A toilet leak can be caused from a multitude of things. To find the cause of a leaking toilet when water is on the floor you always look up. Follow the leak upward until there is no leak. Then look down. For more about this you can check the DIY toilet repair page.
A leaking ceiling that’s caused by a toilet will sometimes not show any water on the floor. If it’s a leaking toilet wax ring then that just requires a wax ring replacement. But if the toilet flange is too far below the floor you may need a flange extension. The wax isn’t meant to seal a large gap. It will sag over only a few years. But sometimes leaking toilet wax ring is due to a loose toilet caused by loose bolts or a cracked toilet flange.
Have you used the garden hose recently?
A burst sillcock can occur when a garden hose is left attached during cold weather. An older sillcock that isn’t frost free needs to be shut off inside the house and drained. But normally you’ll have a frost free hydrant style sillcock. They are specifically designed to drain themselves. This keeps the water pipe far from cold air. But they can’t drain if you leave the hose on. Trapped water freezes. As it freezes it builds pressure. Enough pressure to crack the brass sillcock housing. But a water leak will only occur when the sillcock is turned on. And it’ll leak inside while you’re outside wondering where all your water pressure went.
Have you been using the kitchen sink?
We all use the kitchen sink daily. But sometimes a large amount of water at the ceiling and wall connection can mean a cracked kitchen drain stack offset. The kitchen drain stack is a pipe that runs from under your sink, inside the wall and down to the basement. The kitchen sink is often on an exterior wall. But the wall is sitting on a concrete foundation. So the drain needs to offset about 6 inches to get around the top of the concrete wall. If you have black ABS plastic drain pipes it’s very possible this drain pipe has cracked. And the offsets are a weak point. This is especially true when there’s been settling in a house.
Frozen and burst water pipes
This isn’t a question. During cold weather a frozen pipe can burst and leak in a garage ceiling or along an exterior wall. Shower drains and tub drains can freeze and leak. Cold weather highlights the weaknesses in your home insulation. For more information about this you can go to How to Deal with Frozen Pipes to prevent this.
Leaking plumbing appliances
Normally a water heater will be on the lowest level of the home. This is also true of an hvac system or washing machine. But sometimes they aren’t. So check behind and under the washing machine. Test the drain for intermittent drain clogs. Check the water heater for leaks. They can have thermal expansion that will cause the relief valve to only leak occasionally. And an air conditioner condensate drain can back up. A condensate pan can clog creating water streaks down the side of the a/c. A furnace humidifier drain hose can clog or leak as well.
Some uncommon causes of leaking ceilings
When all else fails you look to the uncommon things. A roof offset near the ceiling leak can mean some roof flashing needs to be sealed. Leaking from a bathroom can be from an improperly sealed shower door or just splashing in the tub. A leak in the middle of the house with no plumbing fixtures around it can mean someone dropped some water on the floor or a water pipe leak or a leaking drain or vent pipe connection. I’ve even seen nails or screws that take years to rust away after penetrating a water or drain pipe.
Who fixes leaking ceilings
Finding the cause of a leaking ceiling is where a good plumber earns his pay. It can be frustrating trying to find the cause. And we don’t want to just start cutting holes in ceilings without being sure. But sometimes it’s all we can do. So in short, don’t hire a handyman for this. And don’t try to DIY this. A ceiling leak should be left to the professionals. Call your local Lees Summit plumber near you. Advocate Master Plumbing will perform a leak detection in a methodical and professional manner while minimizing damage to your home.