DIY Plumbing Mistakes to Avoid

Tackling plumbing projects yourself can be tempting. Fixing a leaky faucet, swapping out a toilet or unclogging a drain often seem straightforward enough, and doing it yourself can save the cost of a service call, right?

Plumbing repairs can quickly become bigger, more expensive problems when something goes wrong. In many cases, what looks simple on the surface hides challenges that can leave even a confident DIYer frustrated.

The Challenges of DIY Plumbing

The first hurdle many homeowners run into isn’t technical. It’s physical.

Tight spaces, old fixtures and stubborn connections can make seemingly simple jobs much harder. Specialized plumbing tools exist for a reason, and without them, removing or tightening components in cramped areas can turn into a long, frustrating ordeal. What you thought would take an hour can easily stretch into an afternoon, especially when corrosion or rust makes old parts difficult to move.

DIYers often run into material issues. Plumbing repairs often require very specific fittings, sealants or adapters. It’s not unusual to get halfway through a project and realize you’re missing something, leading to one or more trips back to the hardware store.

Even small missteps, like choosing the wrong kind of pipe or using the wrong type of thread sealant, can cause leaks that don’t show up until hours or days later.

Common DIY Plumbing Mistakes

Overtightening Connections

It’s natural to want everything snug and secure, but cranking down too hard on fittings, pipe joints or toilet bolts can crack pipes, strip threads or shatter fragile components. These mistakes can create slow leaks that go unnoticed until serious water damage develops.

Using the Wrong Type of Pipe or Fittings

Not all materials are compatible. Mixing PVC with metal, or choosing the wrong kind of fitting without the right adapter, can cause corrosion, leaks or sudden failure under pressure.

Forgetting to Shut Off the Water

Even experienced DIYers sometimes rush into a repair and forget the basics. Skipping the water shutoff can result in gallons of water pouring into your home before you can react.

Relying on Chemical Drain Cleaners

It’s easy to grab a chemical cleaner when a drain runs slow, but repeated use can damage your pipes over time and usually doesn’t address the root of the problem. It also makes professional cleaning harder if corrosive chemicals remain in the line or weaken pipes.

Improperly Sealing Joints

Using too much or too little plumber’s tape or sealant, or applying it incorrectly, can cause joints to leak under pressure.

Misdiagnosing the Problem

Many DIY fixes address symptoms, not causes. For example, replacing a leaky faucet may not fix the real issue if excessive water pressure or a failing valve is causing the leak in the first place. Surface fixes can mask deeper problems that continue to worsen.

The True Cost of DIY Plumbing

One problem with the cost-savings logic of DIY repairs is the assumption that your time is free. In almost no other context do homeowners so undervalue themselves and their finite time.

Let’s consider ‘Bob’, a salesman who makes $100,000 per year (or $48.08 an hour). Bob spends five hours of his Saturday (nearly $250 of his time) replacing his own toilet instead of calling a plumber. As a result:  

• Bob’s house was deprived of a working toilet for most of Saturday, which inconvenienced him and his family.
• Bob had to make multiple trips to Home Depot to buy an ever-increasing number of tools he’ll never use again.
• Instead of enjoying some much-needed relaxation on Saturday, Bob fumed and swore in his cramped bathroom.

Bob also runs the risk of making common DIY mistakes: