How To Add A Bathroom Addition To Your House

How To Add A Bathroom Addition

Delaware is known as the First State. Its rich history is just one thing that makes Delaware a fantastic place to live. But if you own one of Delaware’s older (or even historic) homes, you might be struggling with a simple reality: many older houses just have one bathroom.

A bathroom addition can be a great investment, both in terms of adding value to your house and simply making it more livable. The simplest way to add a bathroom is to tie into your house’s existing plumbing, but if that isn’t possible, you can also add new plumbing and electrical for a bathroom addition. The cost for this type of project will depend on whether you are building a bathroom addition or converting an existing space in your house into a bathroom.

At Carl Deputy and Son Builders, we specialize in building new homes and renovating existing homes in Kent and Sussex Counties in Delaware and the Eastern Shore of Maryland. Our services include bathroom renovations and home additions, including bathroom additions. Reach out today to talk to a member of our design and construction team about your dreams for a new bathroom.

Why a Bathroom Addition Makes Sense

If you have ever had to wait to use the bathroom until another family member is done, then you probably don’t need much explanation as to why adding a bathroom to your house makes sense. Unlike a lot of other spaces, where it is possible to “make do,” having just one (or even 1.5) bathroom can be a real pain. 

It isn’t surprising, then, that one of the biggest reasons to add a bathroom to your house is to make your life better. Whether your family is growing or you can’t stand sharing a bathroom with your teens, adding a bathroom will make your life easier and more convenient. Instead of waiting for your turn to take a shower, you can just go to a completely separate bathroom and enjoy taking your time.

Bathroom additions can also add value to your house. In most cases, a bathroom addition offers a great return on investment (ROI). On average, homeowners recoup 56% of the cost of a bathroom addition when they sell their house. In other words, if you spend $25,000 on a bathroom addition, you can expect to increase the value of your home by 14%.


Of course, doing a home addition is about more than the ROI. You live in your house, and so you want it to be a place that fits your needs. Even if you have no plans to sell your house, putting in a bathroom addition can add tremendous practical and emotional value to your life.

Adding a Bathroom to Your House

Options For Adding A New Bathroom

There are two main options when it comes to adding a bathroom to your house. First, if you have the room, you could potentially convert an existing space into a bathroom (such as a large closet). Second, you can do a home addition to put in a new bathroom.

The first option is far less expensive. Depending on how your house is set up and your material choices, it could cost as little as $5,000 to add a bathroom to a space in your house. Typically, this is done near an existing bathroom so that you can use the same plumbing and vent pipe.

Putting on an addition will be far more costly. Because you will need to physically expand the square footage of your home, it could cost anywhere from $25,000 to upwards of $100,000 to do this work. Given the complexity of this type of project, it should only be done by a licensed professional.

Of course, many homeowners simply don’t have the option to convert an existing space in their home into a bathroom. This is particularly true for older houses, which rarely have large closets or wasted space that could be converted easily. In this situation, it may be necessary to do a bathroom addition.

If your addition is located in the same general area of the house where an existing bathroom is, then your contractor can take advantage of the existing plumbing and electrical systems to keep costs lower. The closer that the bathroom is to the plumbing, the less that you will have to pay to extend water, sewage, and electrical lines. Depending on your house layout, adding a new bathroom above an existing one or near the kitchen can reduce costs.

The total cost of the project will also depend on the other choices that you make when it comes to things like materials. Common bathroom addition costs include:

  • Design and permits
  • Site prep
  • Demolition and temporary support
  • Excavation (preparing the area to run the plumbing, electrical, sewage, and HVAC lines)
  • Foundation work
  • Framing the addition
  • Windows, doors, and siding
  • Drywall and paint
  • Tile and trim
  • Bathroom finishes (such as the toilet, vanity, bathtub, and sink)
  • Plumbing work
  • Electrical work
  • HVAC work

Any add-ons, such as heated bathroom floors, a specialty tub or shower, more expensive tile, or luxury finishes, will increase the cost of your bathroom remodel.

Process For Adding A New Bathroom

Bathroom Design

The process of adding a bathroom to your house starts with the design. We’ll start with the layout, figuring out what type of bathroom you want (such as a half bathroom or a large primary bathroom) and what utilities should be included. For example, if you are adding a first-floor bathroom, you might choose to add a washer and dryer so that you have your laundry on the same level as your house. We can also talk about features, like a zero or low entry shower, grab rails, and wider doorways for a more accessible bathroom. 


Next, we will decide on bathroom placement. This is often the most challenging part of the process, as the most cost-effective option is to add a bathroom near existing plumbing. We can examine various options after doing a walk-through of your house. Generally, it is far less complicated and less expensive to run utilities a few feet through a wall than it is to run them across a house. 


We will also need to consider the capacity of your water supply and sewer drainage lines (or the capacity of your septic system). Local building codes specify the number of toilets that can be connected to a water or sewer line based on its diameter. We’ll consult these codes before advising you on the next steps.

Bathroom Construction

When the design is finalized and permits are secured, we can start construction. Depending on the size of your addition, the process might take anywhere from 6 to 12 weeks. If you are adding a second-story addition or a larger addition, you can expect that the work will take closer to 3 months. For a smaller addition, construction may be complete in a little over a month. Our team will keep you updated on the construction timeline throughout the process.

Many homeowners choose to include a bathroom as part of a larger addition. This can also be a cost-effective choice, as it allows you to increase the square footage of your house and get more space beyond a bathroom. For example, if you put a two-story addition onto your home, then you might gain another bedroom and living area plus a bathroom. While these types of additions can be pricey, they are often a great investment both financially and in terms of your enjoyment of the house.

At Carl Deputy and Son Builders, we work with homeowners to help them design additions that make sense for their budgets and their lifestyles. We will work with you to help you understand your options when it comes to adding a bathroom to your house so that you can make an informed decision. We can also brainstorm ways to keep costs down, such as through careful placement of a bathroom addition or by choosing more cost-effective materials.

If you decide to hire our construction company, you can rest assured that we will complete the project using the finest craftsmanship and attention to detail. We will also provide you with the highest level of customer service, with a focus on open communication. There is a reason why so many of our current clients come to us from recommendations from past clients: we do excellent work and provide great customer service.

Add a New Bathroom with Carl Deputy and Son Builders

A new bathroom can be a great addition to your house. As a practical matter, it is fantastic to have two or more bathrooms in your house. In terms of home value, going from 1 to 2 bathrooms can be a smart choice, particularly if you make cost-effective choices and plan to stay in your house for at least 5 years.

If you are in the market for a bathroom addition in Delaware, Carl Deputy and Son Builders can help. We offer premium quality home addition services to homeowners throughout Kent and Sussex Counties. To learn more about our home addition services or to schedule a consultation with a member of our team, give us a call at 302-284-3041 or fill out our online contact form.

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About Carl Deputy and Son Builders

For 38 years, Carl Deputy and Son Builders has been family owned and operated in Central Delaware. Serving Delaware in mostly Kent and Sussex counties, We have been dedicated to setting the benchmark for quality custom homes and remodeling.

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