How to Find a Leak
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3 plumbers!
When dealing with a water leak, the most frustrating part of the process can often be finding the source. Follow these steps to deduce your leak's source.
So one day you notice signs of water leaking into your house. Maybe you see water stains on the ceiling, mold growing on the inside of an exterior wall or baseboard trim beginning to rot – but where is the water coming from?
I was recently asked to solve a leak in a young couple’s home here in Coconut Grove, Florida. The water was showing up around the inside window trim, so the window was the initial suspect. But there was a bathroom directly above the window, and there was a complicated roof above the bathroom that had a couple of places that could be the source of the leak.
Turns out it was a leak in the shower pan in the upstairs shower that was allowing water to find its way along the second floor subfloor and down along the inside of the outside wall above the window. We found the leak by filling up the shower with water.
We then took a syringe filled with red food coloring-dyed water and injected little squirts of the 'red water' along the junction between the shower floor and the shower wall. When we did this, we could actually see the red water' getting sucked into the cracks, indicating to us that water was 'leaving' the shower through a hole in the shower pan .
So, what can you do to diagnose your leak? Here are some suggestions you can try yourself before you call in a professional plumber:
1. Look up
First check for roof leaks. In most cases, you need to go up into the attic, unfortunately. Sometimes it's obvious, you see the signs of water leaking such dark stains on the underside of the roof sheathing, but not always.
One thing you can do is have someone begin to wet the roof with a garden hose, starting at the eaves and working up the roof. Meanwhile, you, in the attic, look to see if and where, water is making it's way in.
2. Test leak-prone areas
If you suspect a leak from around a window or door, again, have someone wet the window or door [again, from the bottom up] and you look for signs of water coming through the wall.
3. Check the plumbing
With plumbing leaks like the one we found, well, if you think it might be the shower pan (the waterproofing membrane that sits between the subfloor and the tile that comprises your shower floor), you can use the dyed water in a syringe trick.
Or again, just as with a suspected roof or wall leak, begin to think like a detective and look at the plumbing itself. Check for leaks at joints, control valves, and the pipes themselves.
4. Don’t forget about HVAC condensation
Don't overlook the possibility that the water you notice in your home could be coming from condensation of HVAC ductwork that is poorly insulated. and from there, to rot the jambs and trim on the top and both sides of the window.
Good luck, and if you can't find the leak, don't feel bad, sometimes it's not your fault, you just need someone with more experience finding them.
About the Expert Contributor: Tom Southern Builder, in business since 1974, is a home improvement contractor serving Miami and Dade, Broward and northern Monroe counties in southern Florida. Whether it's creating white pine closet shelves that are classy in simplicity, a kitchen that works for the way you live and cook, a post-and-beam back porch, a new energy efficient addition or repairing an old cypress beam, the company is driven to “do it right.”
As of June 26, 2013, this service provider was highly rated on Angie’s List. Ratings are subject to change based on consumer feedback, so check Angie's List for the most up-to-date reviews. The views expressed by this author do not necessarily reflect those of Angie’s List.