As a water heater begins to lean out-of-plumb, it tugs on the two pipes connected to it at the top, along with the flue connector if it is a gas water heater (like the one shown above). A full 40-gallon water heater weights a top-heavy 500 lbs. And the more it leans, the more sideways pressure on those connections. Eventually the pipes will be stressed too much and fracture, causing a flood. 

   Water heaters usually lean because they are on a plywood or OSB platform. Any leakage from the water heater soaks the wood below it, and the weakened wood sags over time. The wet base can also be caused by condensate leakage spreading from an adjacent air handler on the same platform. The problem can often be fixed, after the leakage is repaired, with an additional sheet of plywood under the water heater. Although easier than replacing the whole platform, this fix is not actually all that simple. The water heater must be drained and disconnected from the piping, then reinstalled and reconnected after the platform repair is done. If the water heater is older and corroded, it may be more cost effective to replace it rather than reinstalling it.

   There may also be mold on the interior surface of the drywall sides of the platform that needs to be remediated. And it’s a good idea to add a catch pan, with a drain to the floor of the garage or outside, when you reinstall the water heater. This will keep the same problem from happening again if there is any new leakage. 

    Also see our blog post Are water heaters required to be raised off the floor?

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Here’s links to a collection of more blog posts about WATER HEATERS: 

• Can a Temperature and Pressure Relief (TPR or T&P) valve be mounted to discharge horizontally?

• Where are gas water heaters not allowed to be installed?  

• Is the minimum size water heater inlet pipe 1/2" or 3/4" according to the building code? 

• Can you use a light switch for a water heater disconnect? 

• How can I tell if a water heater is HUD-approved for mobile/manufactured homes?

• Can you wire a 240-volt water heater with 120 volts? 

• Is it alright to have a shut-off valve on both the hot and cold water pipes at a water heater?  

• What is the minimum clearance to doors and windows for an outdoor tankless gas water heater? 

• What is required clearance for access and working space in front of an electric water heater? 

• Why is the water heater older than the house? 

• Does a water heater need a shut-off valve? 

• Why should a tankless water heater have an isolator/service valve kit installed?

• When was a gas water heater first required to be elevated 18 inches above a garage floor?  

• Can the temperature and pressure relief (TPR) valve discharge pipe for a mobile/manufactured home water heater terminate under the home? 

• What is the purpose of a thermostatic mixing valve above a water heater? 

• Does a tankless gas water heater still work with no electricity during a power outage?  

•  Why do water heaters have a sacrificial anode? 

• What is the difference between a manufactured/mobile home water heater and a regular water heater? 

• Does a tankless water heater require a pressure relief valve?

• When is a water heater drain pan required?

• Why is there water in my water heater drain pan?

• What does it mean when a water heater Temperature/Pressure Relief (TPR) discharge pipe is "trapped"? 

• Can I leave a gas water heater in place when remodeling a garage into a family room or bedroom? 

• Where do I find the water heater in a mobile home?

• Does a tankless water heater in an attic require a drain pan? 

• Does an electric water heater require a disconnect? 

• Is a catch pan and drain piping required for a replacement water heater?

• What is the difference between a single element and dual element electric water heater? 

• What is an FVIR water heater?

• What is a dielectric union?

• What's that powdery crust on the pipe connections at the water heater? 

   Visit our WATER HEATERS page for other related blog posts on this subject, or go to the INDEX for a complete listing of all our articles.