10 Bathroom Renovating Mistakes Contractors Wish You’d Stop Making

Focusing on bathroom remodeling ideas is always a great way to kick off your project. But knowing what to avoid is just as important.

We spoke to contractors and custom home builders to get their take on bathroom renovating mistakes you should try to avoid.

Poor Space Planning

Awkward door swings, insufficient clearance around fixtures, or improper placement of vanities and toilets make the space feel cramped and inconvenient.

“A bathroom should be beautiful, but it should also be highly functional,” says contractor Yarin Gani.

And when it comes to small bathrooms, space planning isn’t just a good idea—it’s critical. Where inches matter, good planning can make all the difference between a door that clears the toilet and one that won’t fully open or close.

Gani suggests starting with a solid layout by working with a professional, such as a designer, contractor, or architect. They can help you optimize the flow of the space, ensuring that everything is positioned for comfort and efficiency. 

Want more home reno project tips and inspiration? Sign up for our free daily newsletter for the latest how-tos, reno guides, and more!

Ignoring Ventilation

A major bathroom renovating mistake is not planning for ventilation, says Roi Omer, a contractor with the design-build firm Valley Boutique Builders.

“Since bathrooms are high-moisture environments, adequate ventilation is crucial,” Omer says. “Poor ventilation leads to mold growth, peeling paint, and could lead to structural damage if ignored.”

You can avoid this problem by installing a high-quality bathroom exhaust fan appropriate for the size of the room. 

Also, consider which areas produce the most moisture (such as the shower or tub), so you can position the exhaust fan appropriately.

Overlooking Water Management

Airborne water can be removed with an exhaust fan. But bathrooms also have plenty of water coming from other sources—showers, tubs, or sinks, as well as condensation on the toilet tank and on the walls. 

“Failing to address waterproofing properly can lead to costly issues like mold, mildew, and water damage,” Gani says.

Many homeowners assume standard drywall or low-grade waterproofing are good enough, Gani adds. But cutting small corners here can mean big trouble down the line.

The solution is to invest in high-quality waterproofing membranes behind tiles, especially in the shower or tub area. It’s a relatively inexpensive upgrade that protects your investment for long-term durability, Gani says.

Moving the Plumbing

While you can always move the plumbing around during the bathroom remodel, think long and hard about whether you really need to—and can afford to.

A shower remodel costs $8,500 on average. But if you want to instantly add another $4,000 to the project, move the shower. 

“Moving the location of the shower is where the real money is spent,” says Hendrik Vandepoll, master plumber with Service Force Plumbing.

Ignoring Functionality

“There are many homeowners who gravitate toward stylish and trendy details and items without fully considering how they will function on a daily basis,” Omer says.

Omer says that you can avoid this renovating mistake simply by listening to your contractor and designer.

“Work directly with them to create a layout that takes things like storage and lighting into consideration,” adds Omer.

It’s also important to consider where the plumbing lines will run and the positions of the electrical outlets.

Falling for the Latest Trends

If you try to capture the latest bathroom design trends, chances are good that they might already be dated by the time you are finished.

Whatever the trend—shiplap on the wall, farmhouse chic, contrasting trim, or three-light sconces—steer clear of choosing a trend because it’s a trend.

Instead, go with timeless bathroom designs and elements like premium floor tiles, neutral colors, or hardware that complements the bathroom vanity.

Ignoring Storage

Treating bathroom storage as an afterthought is a bathroom renovating mistake. Bathrooms have such limited space that there’s often little room left for storage.

Consider creative bathroom organizing ideas like:

• Above-toilet shelving unit
• Labeled clear plastic containers
• Tiered organizer
• Freestanding linen cabinet
• Ladder for displaying towels

Choosing the Wrong Materials

“Not all materials perform well in a bathroom setting,” Gani says. “Homeowners sometimes select flooring, cabinetry, or countertops based solely on looks, without considering how they’ll hold up against moisture, humidity, and frequent use.”

Gani notes that installing a wood bathroom vanity or selecting porous stones that easily stain are a couple of prime examples.

If you want that wood vanity, be sure to seal it properly. If you want that porous stone, apply sealant before you use it, as well as every year or so throughout its use.

Even better is to choose durable, water-resistant materials designed for high-moisture environments. 

Porcelain or ceramic tile is a great flooring option, and quartz countertops are low-maintenance and resistant to staining.

Tiling the Shower Yourself

Installing tile can be a fun, rewarding project for a DIYer. With enough time and patience, even a new DIYer can install a backsplash or wall tile in a bathroom.

Since backsplash and wall tile receive limited water, they’re fairly foolproof projects. But installing shower tile is a different matter. 

First, you must choose a wall tile with a low water absorption rate. Next, you must purchase shower floor tile with the correct coefficient of friction (DCOF) value to prevent slipping.

The wall tile needs to be installed so it is perfectly waterproof. Shower floor tile is so tricky for DIYers to install correctly that many opt to install a pre-built, single-piece fiberglass or acrylic shower pan instead.

Not Future-Planning

Omer observes that homeowners typically plan for the moment but don’t plan for the future.

“They often redesign their bathroom based on their current lifestyle,” Omer says.

Instead, they should consider universal design principles, such as wider doorways and a curbless shower to improve accessibility. These features future-proof your bathroom without compromising its current aesthetic.