Should You Install a Bathroom in Your Finished Basement?

While adding a bathroom in your finished basement can be useful and a solid investment, there are some challenges that come with below ground plumbing. You’ll need to consider drainage and ventilation when designing your below-ground bathroom. It’s a job best left to a professional.

Pros and Cons of Installing a Bathroom in Your Finished Basement

As with any home project, there are advantages and disadvantages of installing a bathroom in your finished basement. Consider each one to determine if this project is right for you.

Pros

• Convenient

• Boosts home value

If you decide to transform your finished basement into a kids playroom, a home gym, or a guest suite, adding a bathroom will only improve the space. Your guests will feel more comfortable in their own space and you’ll no longer have the whole family running up and down the stairs to use the bathroom throughout the day. A bathroom in your finished basement is the ultimate convenience.

Adding a bathroom to your basement, or remodeling an existing bathroom, can also increase your home’s value. If you go with a full bathroom complete with a shower or tub, you’ll make the space fully livable. And if you also add a kitchen or kitchenette, you could even rent the space out as needed.

Cons

• Takes up space

• Not DIY-friendly

• Can be costly

If you’re considering installing a bathroom in your finished basement, consider how much space you have. Some basements are as large as the entire footprint of the upper stories of the home, but others are smaller. Keep in mind that adding a bathroom will remove some of that space, leaving less room for your treadmill or the kids’ action figure collection.

Installing a below-ground bathroom isn’t a DIY-friendly project and typically requires a professional who can work out the details. Basement bathrooms come with unique challenges—running water downstairs and back up again can be tricky, so it’s important to hire a professional who knows what they’re doing to ensure that your bathroom works properly.

Because adding a basement bathroom requires a professional as well as new plumbing systems, it can be costly. Plumbing prices vary, but this type of project can easily cost between $10,000 and $15,000.

Go Over Design Options

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First, contact your local building authority to understand what zoning ordinances to consider and to secure the proper permits. Then, plan your basement bathroom’s design.

Decide which style of bathroom you’d like. Your options are:

• Half-bath (toilet and sink only)

• Full bathroom (toilet, sink, and shower or tub)

Half-baths generally work well in basements because they’re functional, but don’t require as much maintenance as full bathrooms. 

Full bathrooms are nice when you’re converting your basement into a guest space. That way, they don’t have to trudge their things upstairs to take a shower. But make sure to add a high-power ventilation fan to draw out excess moisture since basements tend to be damp even without a bathroom.

You should also take your bathroom’s flooring into consideration while designing the room. Bathrooms can be wet, so the flooring you choose needs to be able to withstand exposure to moisture. Vinyl, tile, and concrete are good options.

Consider Plumbing

It typically works best plumbing-wise to install your basement bathroom directly below the bathroom on the upper floor. This will simplify plumbing and eliminate the need for pipes to twist and turn throughout the house, which will require more materials (and more cost).

Talk to a professional about the depth of the sewer line. If it’s deep enough, you can install below-ground water and waste pipes to allow gravity to take care of waste disposal for you. But if it isn’t deep enough, which is a common occurrence, you may need to consider other waste disposal methods, including:

• Sewage-ejector systems

• Upflushing toilet

• Pressure-assisted toilet

If your house has a Pittsburgh toilet—a standalone basement toilet—you can finish a bathroom around it, and you may already have some of the plumbing in place.

Ensure Proper Drainage

It’s crucial to consider drainage when adding a bathroom to a basement. Unlike in above-ground plumbing, below-ground plumbing usually can’t harness the power of gravity to drain waste towards your pipes. Your plumber can help you determine how to combat this issue to ensure proper drainage and waste disposal.

Some basements will have deep drainage lines, which makes waste disposal a bit easier since gravity can get to work. But in cases where those lines aren’t deep enough, you may need to tear up part of your basement floor and dig into the ground below it to create sufficient fall that will encourage proper drainage. 

Your plumber is the best resource here, as plumbing systems vary from home to home. Installing a bathroom in your basement can be difficult and costly, but most homeowners find it to be worth it in the end.