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water seeping into basement cove

Leaking Basement Water Heater

Homeowners don’t realize how reliant they are on their water heaters until problems, such as leaks, arise. What causes leaking basement water heaters?

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If you live in Indianapolis, IN, you are all too familiar with the cold, snowy winters. Although they tend to be short, having hot water during these times is rather important to live comfortably. Unfortunately, as much as we rely on our water heaters, they may sometimes fail and even leak.   

There are two types of water heater tanks present in many homes in Indianapolis: tank water heaters and tankless water heaters. Tank water heaters are the most common and typically run on gas or electricity. 

Due to their sheer size, they are often stored in the walls of basements. Tank water heaters can store an average of 30 to 50 gallons. However, because of this, they are more likely to flood your basement as they contain such high volumes of water. 

Tankless water heaters do not, as the name suggests, hold water inside tanks. In contrast to tank water heaters, tankless water heaters heat water on demand from water that they keep in storage. They use energy only when water is needed. Do keep in mind that, even though water is not held in a giant tank, these can still be prone to leakage. 

No matter which kind you have, it’s important to know what could lead to one leaking, so you can save your basement from an impressive amount of damage. Let’s explore the problem signs that can warn you early, the causes that might lead to a flood, and how you can safeguard your basement against damage from your water heater. 

water seeping into basement cove

What Are the Problem Signs of a Leaking Basement Water Heater? 

Fortunately, many of the problem signs of a leaking basement water heater are easy to find, especially before the problem gets worse. Check out these common indicators that your water heater is leaking:  

  • Damp Basement Walls and Floors 

Damp spots on your basement walls or floors are the earliest warning signs of a leaking basement water heater. If you find that the walls and floors are damp around your basement water heater, your water heater is likely the culprit.  

  • Mold and Mildew 

Mold and mildew are two types of fungi that thrive in wet or humid environments. Depending on how long your basement water heater has been leaking, you may find mold or mildew growing around it. The amount of mold and mildew that has grown is correlated to the amount of time that your water heater has been leaking. In short, more leaking means higher chances of mold and mildew growth. 

  • Pests 

Many household pests, especially insects, are drawn to dark and isolated environments, such as your basement. With a leaking water heater, this can increase the humidity levels within your basement, making your basement even more inviting than if it were dry. Some of the most common pests that are drawn to wetter environments include, but are not limited to: 

  • Cockroaches 
  • Earwigs 
  • Silverfish 
  • Centipedes 

Although they much prefer the isolated, humid conditions of your basement, they may emerge from time to time inside your house for food. If you notice that you are having pest problems when you have not before, it may be a good idea for you to check your basement to see if that is where the bugs are coming from. 

  • Water Heater Cracks 

One of the more obvious problem signs of a leaking basement water heater are cracks on the heater itself. Water heater cracks are more likely to develop in tank water heaters, however, tankless water heaters can form cracks too, depending on the condition of the water heater.   

  • Basement Floor and Wall Cracks 

Cracks found on basement floors and/or walls typically follow long exposure times to water, which can happen if leaking basement water heaters are left unchecked. When certain materials are exposed to water, they can become weakened or even degrade over time. Additionally, if more water enters the basement wall or floor cracks, the cracks may become more elongated, or spread to other areas. Softer materials, such as paper-based wallpaper or drywall, are more likely to develop cracks. 

What Causes Leaking Basement Water Heaters? 

Many of the causes behind a leaking water heater require you to examine it in different areas of the water heater itself. Understanding what causes leaking basement water heaters in the first place is the first step towards finding the appropriate solution:  

  • Rusted Valves and Connections 

Rust can form on certain water heater valves and connections in the presence of high humidity levels or continuous exposure to water. In Indianapolis, IN, humidity levels are highest in December, when snow accumulates outside. Basements are not built to keep humidity levels out without supplementary appliances. Humidity levels can rise in your basement, paving the way for rusting. 

Rusted valves and connections can become loose or even faulty over time, which can result in leakage from your basement water heater. Certain water supply tubing in water heaters are more prone to leakage than others. There are two common types of water supply tubes: flexible and rigid. Flexible water supply tubes tend to develop rust and wear out faster than rigid water pipes do. The more rust your water supply tubes have, the more likely it will loosen and leak. 

Rusting is much more likely to occur in tank water heaters rather than tankless water heaters. This is because many tankless water heaters have stainless steel water supply pipes. However, this does not mean that tankless water heater connections will never rust. Stainless steel can still rust, depending on the chromium content. The more chromium that stainless steel has, the more protected it is against rusting. 

The drain valve is another part of your water heater that may become loose or faulty due to rusting. The drain valve is responsible for draining the water supply from inside the water heater tank. This is usually done manually. Therefore, a drain valve that is functioning normally should not have any water leaking from it. Water leaking from your water heater’s drain valve is indicative of either a loose or faulty valve that must be replaced.  

  • Collection of Sediment 

You may be wondering how sediment can even accumulate in your water heater. Sediment can form naturally within your basement water heater after continuous cycles of water heating. Over long periods and repeated water heating, this mineral can build up at the bottom of your water heater. Some homeowners may be familiar with water “hardness”. It is this collection of sediment over time that contributes to the “hardness” of your water supply. 

Although sediment accumulation in your water heater is not necessarily dangerous, it can ruin your water heater’s integrity and its ability to function effectively. If you notice that your water supply is taking longer to heat or that it is not supplying as much hot water as before, sediment collection in your water heater tank may be the cause. You may also notice discoloration in your home’s water supply. An excess amount of sediment inside your water heater can deteriorate and corrode your tank. This corrosion can damage your water heater from within, causing it to leak and possibly flood your basement.  

  • Excess Water Pressure or Temperature 

Although your water heater is built to withstand high water temperatures and pressure, any steam or water temperature that crosses a certain threshold can result in pressure buildup in water heater tanks. This pressure buildup can force water out through any loose connections or openings, such as cracks or holes. In excess, water will leak out of your water heater. In more extreme cases, this intense pressure buildup will cause loose valves or connections in your water heater, resulting in even more leaks.   

Normally, the temperature and pressure relief valve—better known as the T & P valve—can regulate both the temperature and pressure of the water within your water heater tank. It does this by draining some water out of the water heater. This is not considered to be leaking, as this is normal maintenance. However, if water continues to leak out of your water heater’s T & P valve, it may be experiencing high water temperatures and pressures. It may also be faulty. 

Because of this, homeowners should take extra precautions when increasing their water temperature, especially during the colder seasons. If you notice that your T & P valve is continuously leaking throughout the winter months, you may have to keep your water temperature lower than what is ideal until you can get it repaired.  

  • Internal Leaks 

Regardless of whether you have a tank or tankless water heater, internal leaks can occur. However, both the location and the reason they result in external leaks may differ. 

Tank water heaters are often built with two layers. The first, outer layer is the metal shell that you can see. The second layer is inside the water heater, which is surrounded by insulating material to help retain the temperature of the water. This is crucial for providing hot water throughout your household.   

Unfortunately, leaks can spring from this second layer. When this happens, the insulating layer can become soaked, preventing your water heater from working properly. Although you may not be able to see internal water heater leaks, you may be able to feel the effects of an internal leak. If you notice that your water temperature is not as hot as you are used to, this may indicate that your tank water heater has sprung an internal leak. 

Tankless heaters can spring internal leaks if there are any venting failures. Vents are most important in tankless water heaters that run on natural gas or propane. Proper venting allows the byproducts of heated natural gas and propane to escape, as well as preventing condensation accumulation, ensuring that the water heater functions normally. In the event of impaired vents, condensation can collect within the water heater, resulting in leaks or even water heater failures. 

When left unchecked, internal leaks can cause water to pool underneath your water heater and onto your basement floor and walls. This can occur for both tank and tankless water heaters.  

  • Old Age 

Unfortunately, our basement water heaters are not meant to last forever. Even with the utmost care, a water heater can cease to function properly with age. When this happens, water heater leakages may not be far behind. 

This is why checking on your water heaters from time to time is important. It is easy to forget about them since they reside in your basement, but proper maintenance is required to maximize the longevity of your basement water heater.   

How Can I Fix Leaking Basement Water Heaters? 

Fortunately, leaking basement water heaters are not too difficult to repair. The Indiana Foundation Service provides a variety of solutions that address both your leaking water heater and damaged basements that may result from it.  

  • WallSeal™ Basement Wall Vapor Barrier 

The WallSeal™ basement wall vapor barrier is a patented waterproofing system that can be installed directly onto your basement walls. Since many water heaters are installed within basement walls, having the WallSeal™ will prevent water damage and musty smells that may accumulate from a leaking water heater. It is 100% waterproof with a sleek, white, modern design that can fit around even the most irregularly shaped walls. The material is also mold resistant so that you no longer have to worry about mold and mildew festering in your basement in the event of a leak. 

  • Interior Drain Systems 

The Indiana Foundation Service offers numerous interior drain systems that can be installed right inside your basement. Two kinds can be installed to address basement water heater leakages, so you can select one that fits your needs and budget accordingly. 

The BasementGutter™ below floor drain lies on the perimeter of your basement, collecting and draining any water that accumulates in your basement. It is conveniently installed underneath your floor so that you do not have to worry about it being invasive, and in an area that guarantees clogging will not happen. 

The grated drainage pipe is the simplest interior drain system. Upon installation, it easily melds into your basement floor, so that you will not be concerned with tripping hazards. It accepts water that floods into the floor and redirects it to your perimeter drain systems. 

Leaking Basement Water Heater


Determining whether you have a tank versus a tankless water heater in your basement is crucial in determining the potential cause of water heater leaks. It is also helpful when you are seeking out solutions so that you find the repair that works best for your water heater.  

  • Tank Water Heaters 

Tank water heaters are typically larger compared to tankless water heaters—containing a volume ranging between 30 to 50 gallons of water. They are the most common and have been around for a much longer time. When you think of water heaters, a large, cylindrical tank sitting in your basement or garage wall or closet may come to mind. If you have something like this in your household, you most likely have a tank water heater. 

Tank water heaters are constantly running to heat your water supply. These water heaters typically run on gas or electricity. The longevity of tank water heaters is much shorter than tankless water heaters, and average a lifespan of 10 to 15 years.  

  • Tankless Water Heaters 

Tankless water heaters are significantly smaller in size than tank water heaters. As such, you may find that it is stored in various places, not limited to your basement. Due to its’ smaller size, you may find that it has been installed inside closets. Tankless water heaters tend to have a boxy, rectangular shape to them, rather than the cylindrical shape that tank water heaters do. 

Tankless water heaters heat water on demand, which is why they do not take up as much space. They use energy only when necessary and can run on either natural gas, propane, or electricity. Tankless water heaters have a longer life span compared to tank water heaters by at least double, averaging at about 20 to 30 years. Tankless water heaters are also less likely to leak, however, leaks can still occur depending on the age and condition of the water heater. 

Repairing any appliance that runs on gas or electricity is dangerous. As such, it is highly recommended that you do not, under any circumstances, perform water heater repairs at home. You may exacerbate the problem or, in the most extreme cases, put yourself in potential danger. 

  • Dangers of DIY Water Heater Repairs 

Regardless of whether you have a tank or tankless water heater in your basement, tampering with any of the connections, valves, or piping is never a good idea if you do not know what you are doing. Your water heater is built to contain and move large volumes of water. Attempting to readjust or repair your water heater yourself can make a minor leak become a major one. This can lead to intense basement flooding, resulting in even more costly damages. 

Furthermore, if your water heater is located near any electrical appliances or units, DIY repairs can cause water to enter these electrical areas. This can potentially spark electrical connections and cause an electrical fire. 

  • How to Maintain Your Water Heater at Home 

While you may not be able to repair leaking water heaters in your basement yourself, you can certainly try to maintain them after getting them fixed. Sediment will inevitably collect in your water heaters. Flushing out sediment from your water heater will increase its longevity and prevent internal leaks or damages. You may want to contact a contractor to do this for you initially so that you can learn how to so safely and properly. However, even something seemingly simple as flushing out your water heater has its risks for increasing damages, so if you are uncomfortable doing this, rely on the experts to help you. 

You should also perform routine checks of your water heater’s connections, valves, and piping. While they are certainly built to last, they can still experience wear and tear. Check to see if any parts are leaking. They may need to be replaced. 

Not at all! As long as you take care of your water heater, costly repairs are a one-time expense that can help your water heater last a long time. Considering preventative measures may lower the risk of needing more repairs even more. 

  • Preventing Humidity and Moisture 

Rusting is one of the major culprits of water heater leakages. It can result in loose valves and connections in your water heater, which contributes to leaks over time. Rust is often a problem in humid environments. Therefore, if your basement tends to be humid, either in the summer or winter, you should consider waterproofing. 

The WallSeal™ Basement Wall Vapor Barrier is very useful in that it combats moisture from accumulating in your basement, as well as all the side effects that come with it. These side effects include mold, mildew, pests, and water damage. A bonus benefit is that it brightens up your basement.  

  • Preventing Water Accumulation 

Even if you have waterproof systems, such as the WallSeal™, leaks may still occur. Having efficient drainage systems in your basement is a must to prevent water accumulation. 

The two most common drainage systems in basements are sump pumps and interior drains. Interior drains can collect water from your basement floor and redirect it to your sump pump. The sump pump then moves this water away from your house and to an external drainage area. 

Seek out Your Local Experts for Leaking Basement Water Heater Issues 

Leaking basement water heaters are not fun to deal with. They bring a lot of problems, such as mold, pests, and damages, and DIY repair is out of the question. The good news is, you can reach out to Indiana Foundation Service to help you identify the causes at play and safeguard your basement against damage. We offer free inspections and no-obligation quotes, so you can get a full look at what any possible repairs or waterproofing solutions would be long before you need to take action. Contact us to schedule your free inspection today! 

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