Water Heater Leaking From The Bottom? (Causes & Cost to Fix)

Water Heater Leaking From The Bottom

Leaks are something that almost every homeowner fears, if only because of the extensive damage it can cause due to mold. When it comes to your water heater, a leak can be a total nightmare to deal with. Water heaters that leak can cause your energy bills to skyrocket while also causing mold and mildew damage. If you notice your heater leaking from the bottom, you would be forgiven if you panicked. But, what can cause this?

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The most common cause of a water heater that leaks from the bottom is old age. Since water heaters have a tendency to rust over time from sediment buildup at the bottom of the tank, the corrosion from the rust eats away at the tank. This eventually eats a hole in the bottom, causing water to leak.  Replacement is the only option here.

If you recently noticed a little dripping from the bottom of your water heater, now would be a good time to take a look and see what the cause could be. This guide will help you figure out how to fix things up and hopefully understand why this happened in the first place.

Why Is My Water Heater Leaking From The Bottom?

With most heater leaks, it’s possible to trace your problem to a bad valve, or maybe a bad pipe. Sometimes, it might even just be something as simple as a screw that went loose. This is not the case with a heater that’s leaking from the bottom. This is almost always a case of a heater “dying from old age.”

As water heaters continue to be used, sediment and impurities in the water will build up in the bottom of the tank. As they build up, they start to corrode the tank from the inside out. Eventually, the corrosion will cause a leak. Since the corrosion is coming from the inside, trying to repair it won’t work.

How Long Does It Take For A Tank To Start Leaking From The Bottom?

This all depends on the purity of the water in your district as well as the build of the water heater. Generally speaking, most water heaters will start having a risk of leakage after about 10 to 13 years. That’s one of the primary reasons why experts suggest replacing a water heater every 10 years or so.

Why Can’t You Fix A Water Heater That Leaks From The Bottom?

With most leaks, you can replace a valve or add a patch, but this isn’t the case with a leak that’s caused by corrosion. The corrosion means that the leak will come back, even if you try to patch it up. Moreover, there’s a good chance that the bottom of the water heater’s tank won’t be able to handle a typical repair.

Could The Leak Be Something Other Than The Tank?

If you have a tankless system, the leak you’re seeing clearly isn’t from the tank. In most cases, the leak is caused by corroded piping or similar problems. Since corrosion is still the likely culprit, the cause may be different by the cure will remain the same in many cases. However, if you believe it could be a fixable issue (such as external piping that’s leaking), you should call a plumber to see if it can be fixed.

How Can You Prevent Your Tank From Leaking At The Bottom?

An ounce of prevention is worth a pound of cure when it comes to keeping your water heater intact. If you want to avoid having a leak at the bottom of your water heater, there are a couple of things you can do to prolong your heater’s life. These include:

  • Perform a maintenance check on a regular basis. It’s amazing how much a little TLC can do for your water heater, and yet, we very rarely actually take time to maintain our heaters. By keeping an eye on your heater, you can spot problems and fix them before they get to become troublesome.
  • Drain and flush your heater annually. This is what will reduce the chances of your tank building up sediment or having issues with hard water. If you have been dealing with a fickle water heater, it may even be smarter to flush out your heater more than once per year.
  • Replace your anode rod once every three years. With most modern water heaters, the water heater is protected by something called an anode rod. This small rod is there to help slow down the corrosion of the tank, and in most cases, it loses its effectiveness within three years. If you leave the anode rod alone, you will start to see your water heater tank corrode faster and faster. So, switch it out.
  • Choose a water heater that’s known for durability. Like with any other type of household appliance, getting a water heater that is known for being cheaply made will result in faster corrosion and a need for repairs. A water heater is not something that you should buy lightly. If you need to get a new heater, make sure to treat it like an investment. Why? Because it is, and because repairing a busted heater three times a year isn’t something anyone wants to do.
  • Don’t use corrosive chemicals or store caustic items near the water heater. Do you have a water heater in a workshop? If so, be careful of what’s around you. Exposure to corrosive chemicals, especially ones that are stored improperly, can lead to corrosion that happens from the outside in.
  • Consider buying a tankless system. Since tankless systems are not going to have corroded tanks, this is one way to make sure that you avoid having this problem in the future. That being said, quality matters here too. When choosing a tankless system, read up on reviews to find out what they have to say.

How Much Does It Cost To Replace A Water Heater?

It all depends on whether you get a professional water heater replacement done, or if you want to try it on your own.

Before You Buy A Replacement Heater…

Before you decide to shell out cash for a replacement, you might want to call your manufacturer to see if your warranty or heater’s guarantee will cover repairs. That way, you have a shot at saving serious cash. The vast majority of water heaters have a five to 10-year warranty, so you definitely could have a shot at getting your heater replaced if your heater broke early.

Going The DIY Route

If you go the DIY route, the cost will be the same as the price of the water heater that you choose to install. Depending on the type of heater that your home requires, going the DIY route means that you can expect to pay $450 to $1,000 for a standard replacement. Because replacing a water heater takes a lot of skill and experience, this is not something that the average DIYer should attempt on their own.

People who decide to invest in a tankless water heater will see the price get a little higher. Tankless systems typically start around $800 and cap out at around $3,000.

Going Through A Professional Route

Going through a plumber to get your water heater replaced will be a little pricier, but it’s a good way to ensure that you get your heater replaced properly. The overall price can change depending on the water heater type as well as the location where you live. On average, getting your new heater installed can cost between $1,000 to $2,000. The average price for a tank water heater, nationwide, is $1,500.

If you want to install a tankless system in your home, there’s some good news and bad news. The good news is that they are far less likely to have bottom leaks. Those that do leak near the bottom tend to have the leaks caused by piping issues rather than tank rot. The bad news is that the price of a professional install for a tankless system ranges from $1,250 to $5,000. So, it’s a lot more expensive.

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Our Final Take

If you notice that your water tank is leaking from the bottom, it’s a pretty bad sign. In the majority of cases, a bottom leak suggests that the tank has been corroded from the inside. This means that most leaks of this kind can only be fixed by replacing it with a brand new water heater. This is not always avoidable. Most tanks will start to leak around the 10-year mark, though it’s possible to delay it by carefully maintaining your heater.

If your tank started to leak within six years of its purchase, call your manufacturer. You might be able to get some free repairs. If it’s a matter of “dying of old age,” then you should expect to pay around $1,000 for a DIY replacement, or several thousand dollars for a plumber to replace your heater. Sadly, this isn’t a repair that you can skip out on. Without a water heater, you really can’t use your water at home.

Ossiana Tepfenhart

Ossiana Tepfenhart is an expert writer, focusing on interior design and general home tips. Writing is her life, and it's what she does best. Her interests include art and real estate investments.

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