How Much Does It Cost to Add a Bathroom to Your Home?

Reviewed by Dan Simms remodeling expert. Written by Fixr.com.

The average cost to add a bathroom to your home is around $25,000 if you’re able to convert an existing space that already has some plumbing hookups, like a laundry room. If you’re building an add-on to house your new bathroom, your total is going to sit closer to an average of $55,000. Most homeowners can expect to pay somewhere between $18,000 and $90,000 to add a bathroom.

Quick Takeaways

• The average cost to convert an existing space to a bathroom is around $25,000, which includes framing out the walls and installing a bathroom from scratch.

• Building a home addition for your new bathroom will be much more expensive, and at that point, adding extra rooms and square footage at the same time will be more cost-effective.

• If you can use existing plumbing in a space that’s already framed out, you could pay as little as $18,000 to convert it to a bathroom.

Factors That Affect the Cost to Install a Bathroom

The cost to add a bathroom varies so widely because there are many things that can affect your total, some of which can swing prices by tens of thousands of dollars. Be sure to consider all of the following cost factors to get a good idea of where your budget needs to be.

Location in Your Home

One of the most impactful cost factors when it comes to installing a new bathroom is the location of the new room in your home.

Building a home addition to house your bathroom is going to be the most expensive option, by far, as it includes laying down a new foundation, framing out the addition, adding exterior walls, siding, roofing, and windows, connecting the add-on to the rest of your home, and installing new wiring and plumbing to the add-on. Only then can you start allocating the rest of your budget toward actually installing the bathroom components. 

If you’re building an add-on for your bathroom, expect to pay an average of $55,000 to $90,000, depending on the size, foundation type, quality of materials, and other factors. In most cases, building a larger add-on that includes bathroom space will be more cost-effective than just building an add-on for a bathroom.

Walling off a portion of a bedroom or common area to create a bathroom will be the next most expensive option, but your total will pale in comparison to what you’d spend to build an add-on. 

You’ll need to pay between $750 and $2,000 to frame out the area and another $3,000 to run the necessary wiring and plumbing to the room. After that, your professional will need to demo the flooring and drywall, install cement backer board, then build out the bathroom. The bathroom installation will cost an additional $21,250 for a full bathroom, plus the average of $3,750 you’ll pay to frame the area and run utilities to it.

The most affordable option will be installing a bathroom where you already have framing and utility connections, like a laundry room or a space right above your utility room. Running drain lines and water supply lines to the area should be easy and may not even be needed at all, so you’ll save close to $4,000 on the total.

One other factor to consider is the added cost of installing a bathroom in a basement. Walling off an area of your basement and running utility lines will cost about the same as they would elsewhere in your home, but since the bathroom will be located lower than your main sewer connection, you’ll also need to install a sump pump to direct wastewater up through a waste line so that it can eventually drop into your main sewer line. 

Installing a sump pump for a new basement bathroom will add around $1,200 to your bathroom addition costs, bringing the total cost to add a basement bathroom to $26,200.

Type of Bathroom

The type of bathroom you install will play a role in your total costs, too, as different bathroom types have different requirements for fixtures and amenities.

The cost to install a half bathroom or powder room sits between $6,500 and $10,500, including the cost to wall off an existing area of your home, fit it with utilities, and then install the appropriate amenities. A powder room typically only has a sink and toilet, while a half bath can also have a stand-up shower stall.

A full bathroom, which includes a sink, toilet, and a shower/tub combo, will cost between $11,500 and $26,000 to install in a pre-existing area in your home.

Installing a master bathroom, which may include both a bathtub and a shower, as well as at least one sink and a toilet, will cost between $19,000 and $42,000 to install in an existing space and up to $68,000 or more if you’re building a home addition to house your new bathroom.

Bathroom Size

Most bathroom renovation projects can be more or less accurately priced out using an average cost per square foot, which can vary based on materials and labor options. 

Generally speaking, expect to pay an average of $275 per square foot to install your bathroom, plus an additional $80 per square foot to frame out the room and run the necessary utility lines. That brings you to an average of around $355 per square foot to install a bathroom in an existing space.

If you’re building an add-on to house your new bathroom, expect per-square-foot prices of around $600 for building the actual add-on, plus the $275 per square foot you’ll pay to install the actual bathroom components. That brings you to a total of $875 per square foot.

In either case, the size of your bathroom will determine the total installation cost. You can use the table below to get a rough estimate for your project using these numbers. For reference, 20 sq. ft. is a typical half bath size, a 50-foot bathroom is an average full bath, and a bathroom over 100 sq. ft. is a large master.

Components

For the most part, your bathroom installation costs will be determined by where you install your new room, what the existing area looks like, and the type and size of the bathroom you’re adding. However, there are still other options that can affect your pricing, like choosing a custom walk-in shower over an alcove bathtub/shower combo in a full bathroom.

If you have your bathroom remodel ideas in your head already, you can get a rough estimate for your total installation costs based on the information above — the $4,000 to add utilities and wall off an area and the $30,000 to build a home add-on for your new bathroom — in addition to the table below, which includes pricing for installing different components and amenities in your new space.

Material Quality

As with any home improvement project, opting for high-end materials means paying high-end prices. For example, vinyl flooring is usually much cheaper than natural stone flooring and some custom tile flooring options. Similarly, installing chrome or plastic faucets is usually far more affordable than getting fixtures crafted from copper, nickel, or brass. You could reduce your new bathroom costs by as much as 20% just by opting for more affordable materials.

That said, there are good reasons to opt for luxury materials if you can afford them. More expensive fixtures and flooring tend to last longer, so you usually don’t have to replace them as often. This means paying more now can save you money in the long run. 

Additionally, more luxurious materials will elevate the aesthetic of your new bathroom, which means you’ll be adding more to your home value by choosing high-end materials.

Labor

Labor accounts for around 50% of the cost to add a bathroom to an existing space in your home and as much as 75% if you’re building an add-on to house your new bathroom. On average, building a bathroom in an existing area of your home will include around $13,000 in labor, whereas building a new add-on and a bathroom can cost as much as $41,250.

Even though the labor costs are expensive, it’s best to leave this work to the professionals rather than try to DIY your bathroom remodel. Constructing a bathroom requires a high level of precision and expertise, so even avid DIYers can quickly find themselves in over their heads. 

Plus, most municipalities require building permits for new bathroom additions, and you’ll likely find that your building department requires that you hire certified plumbers, electricians, and bathroom remodelers to get the permit process started. As such, you’ll likely have to hire professionals to do a big portion of the work, especially if you’re building a new home addition for your bathroom.

How to Pay for Your New Bathroom

Installing a bathroom in your home can very quickly get out of hand in terms of cost. Luckily, there are a few different financing options you can take advantage of.

Your first option is to finance through your installer. Many, but not all, bathroom remodelers offer in-house financing plans, meaning you might be able to make a payment plan with the company that installs your bathroom instead of searching for third-party financing. Be sure to check the fine print, though, as your installer’s financing may not be best for your situation.

Your next option is to take out a loan. This could be a personal loan or a home equity line of credit (HELOC). With either type of loan, you get a lump sum of money that you have to pay back with interest. Personal loans typically have steeper interest rates, so they can take longer to pay back. 

Home equity loans can be a little more risky, though, because they’re secured by the equity you have in your home. This means that if you default on your home equity loan, you could face foreclosure.

Your last option is to opt for a renovation loan, also called an FHA 203k loan. This is an alternative to a standard mortgage, so it’s only an option if you’re in the process of buying a home and know you want to do work on the house after closing. 

With a renovation loan, your lender gives you more money than the house is worth in its existing condition and more than the seller is asking for the house, with the understanding that you’ll use the excess funds to renovate the home and improve its value. 

There are restrictions and regulations you’ll have to consider, but this is a solid option if you’re buying a home and want to add a bathroom.

Other Factors to Consider

There are a handful of other factors you should consider before moving forward with this project, some of which can have an impact on your total bathroom installation costs.

Permits and Building Codes

Part of the reason it’s so beneficial to hire professional general contractors to install your bathroom is that the construction requires permits. You must also ensure everything in the bathroom meets local building codes. 

Contractors know how to navigate all this red tape and keep the installation to code, so you don’t have to worry about the research and planning nearly as much.

You will have to pay the permit fees, though. If you’re installing a new bathroom in an existing interior space, your permits will likely cost between $250 and $600, depending on your local building department’s fee schedule. If you’re building a home addition to house your new bathroom, your permits can cost between $500 and $2,000.

More Bathrooms, More Plumbing

With another bathroom in your house, you’ll have additional water supply lines and drain lines. If you already have an issue with low water pressure, adding another bathroom could make the problem worse. If you’re on well water, you could install a booster pump to create more pressure, but this will cost an average of $1,200.

If you’re on a septic system, the added waste capacity could be problematic. You may need to upsize your septic tank — which costs an average of $8,000 — or pay for septic pumping more frequently, which costs between $300 and $600 per instance.

Effect on Home Value

Finally, you should consider the effect your new bathroom will have on your home value. If you’re installing an add-on for your bathroom, chances are the added square footage will far outweigh the loss of yard space in terms of value. 

If you’re installing a bathroom in an existing space, though, you may want to speak with a local real estate agent to see if the space would better serve home value as bedroom space or general living space.

FAQ: How Much Does It Cost to Add a Bathroom?