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How to Find a Water Leak Inside a Wall

One of the biggest causes of wasted water in your home is a slow leak in your pipes, plumbing fixtures and appliances, especially water leaks behind walls. Because these leaks are generally silent, they often go undetected.

If left untreated, hidden plumbing leaks can lead to serious water damage in your home. But there are usually some subtle signs to help you identify these types of leaks, including:

  • Mold or mildew. Mold thrives in moist, dark areas, which are typically hidden behind walls or under flooring. If a pipe springs a leak, mold can begin to grow in the area. If you see mold in unusual places where water does not usually accumulate, such as non-shower walls, you may have a leaking pipe.
  • Peeling paint or wallpaper on your walls.
  • A wall that is warped or stained for no apparent reason.
  • A buckled, cracked or water-stained floor or ceiling, especially in your bathroom.
  • A musty smell. Old, accumulated water from a leaky pipe tends to have an odor. And if it’s behind a wall, it never has a chance to dry."


Plumbing leaks can happen at any time. While a small leak can be a nuisance, in many cases, it is not a difficult problem to repair, if you have the right understanding of how to repair plumbing leaks.

We have compiled a list of helpful tips below from the industry experts, so you can be prepared in the event of a plumbing leak in your home.

Here are a few things you should know about how to repair plumbing leaks in your home:


It is always a good idea to have an idea of how much water you and your family use on a monthly basis. Having a general knowledge of your water usage, by periodically checking your water meter can help you to see if you have a leak somewhere in the house.

The Environmental Protection Agency noted that if a household of 4 finds that it's using more than 12,000 gallons per month during cooler seasons, this is a sure-fire sign of serious leaks.

Even a small leak can rack up giant water bills if not repaired quickly. The EPA found that leaks in homes across the country waste as much as 1 trillion gallons every year! This is the equivalent of regular water usage in more than 11 million homes. Address leaks promptly and don't let that water drip onto the ground or run down the drain – repairing plumbing leaks quickly will help to conserve this important resource.


If you do not find any obvious leaks from your water-using appliances, you most likely have a hidden plumbing leak. Signs of hidden leaks in your plumbing system include: mold or mildew, damaged paint or wallpaper, damaged walls or flooring, stains on ceilings, or a persistent musty or earthy smell. If this is the case, we recommend calling your local Roto-Rooter plumber immediately to prevent any further damage to your home.

If you need a professional to check for hidden leaks, you can rely on Roto-Rooter’s leak repair professionals to locate and repair every type of water leak in and around your home.


It's critical to know where the main water shut-off valve is located in your home. HouseLogic pointed out that if there's ever a leak anywhere in the house, you can use the main shut-off valve to cut off the water supply to the entire home- immediately.


It can also be helpful to have shut-off valves installed around your house. Additional shut-off valves are inexpensive items, with most selling for under $10. Installing additional valves can allow you to shut off the water in certain areas of your home for repairs, while keeping it running in other rooms. With additional valves, someone can still shower while you're fixing the kitchen sink.


Most people are familiar with the symptoms of a clogged toilet, but smaller toilet leaks can be harder to identify. They can lead to the largest amounts of water being wasted.

Leaks near the toilet can be a bit harder to identify, especially if they are inside the toilet's flushing system.

A common small leak can occur where the toilet tank leaks into the bowl. When you flush, the water only shuts off to the toilet tank when the water level passes a certain point. When there is a leak, the water will just keep running. To diagnose a leak like this, add about 6 drops of food coloring to the tank, do not flush the toilet, and wait 30 seconds. Open the lid to the toilet bowl, and if there is any amount of coloring present, your toilet is leaking and requires repair. (It is important to not try this method for other types of leaks, as the food coloring can stain other materials.)

Often, a toilet's flapper or valve seal can be the culprit for a toilet leak. This small rubber part can decay if it hasn't been replaced in a while, or might not fit exactly right if minerals have built up. Flappers and valve seals are relatively simple and inexpensive to replace – with the water turned off, of course.


Some leaks are easier to repair than others. For tougher jobs, it's important to consult a plumbing professional to ensure that things are fixed correctly, the first time.

For more information regarding your residential plumbing, including installation and repairs, contact your local Roto-Rooter plumbing expert today.


There are many obvious signs of water damage, including burst pipes, an overflowing toilet, water heater failure and sump pump failure. However, don’t forget about the possibility of a hidden water leak. These can silently damage your home. Tracing a hidden water leak can be difficult, but it is necessary to take steps to avoid the potential damage that a water leak can cause.

As a homeowner, you can detect signs of water damage with these five tips from Roto-Rooter:

1. Examine the Walls

Check your walls, as well as ceilings and window and door frames for water damage signs. Also look for stains or cracks on your drywall and any area that may be soft or swollen.


Infrared cameras function much like regular cameras, except that rather than recording how much light reflects off of objects, they reflect how much heat an object emits. Infrared is also capable of seeing cold or warm objects through thin walls. Infrared cameras are useful for locating leaks within walls because the wet areas will be colder, making them visible through the camera. Infrared cameras are an expensive investment for the average homeowner, so it’s unlikely you’ll ever want to own one yourself, but some companies will do an infrared scan of your home for you.

2. Investigate the Floors

Check your floors, especially in the basement, for signs of buckling. Any indication of warped flooring usually means water damage is present. Also, be aware of stains on your carpeting or wood flooring. Damp flooring could serve as a breeding ground for mold and mildew.

3. Survey the Pipes

Inspect piping in your laundry room, bathroom, basement and kitchen for water stains. Make sure you also survey your water heater for rust on the tank and damp spots on the floor.

4. Check the Attic and the Roof

Pay attention to the areas where your roof’s decking boards meet, inspect the areas around chimneys and vents, and where the roof comes together with the walls. Make sure that the insulation throughout your attic is in good condition and is dry.

5. Analyze the Exterior

Investigate your roof for missing shingles and monitor any standing water. Examine the valleys in your roof and the flashing around chimneys and vents. Make sure your roof gutters aren’t pulling away from the edge of your house.

The harmful effects of water damage can be reduced greatly by the prompt and reliable plumbing and water damage restoration services from Roto-Rooter. Call us when you notice the signs of water damage, and we will send a specialist to get your home back into working order as soon as possible.


If you aren't sure whether you have a leak or not - or you know you have one but you aren't sure how to fix it - a local Roto-Rooter professional can help. He or she will be able to track down the leak and repair it quickly