top of page

How to Add a Bathroom to Your Home

Updated: Apr 19

Ever see the Portlandia sketch called "Put a Bird on It?" It humorously satirizes a popular trend in arts and crafts culture, where adding a bird illustration or motif is seen as a quick and quirky way to make any creative project more visually appealing. Well, in the realm of home improvement, the little voice in the back of my mind is perpetually coaxing: "Put a Half Bath In." All you need is approximately 5' x 3' of space!

Designing a small bath within a confined space isn't a limitation – every inch becomes an opportunity to craft a luxury, where thoughtful design choices resonate with purpose and elegance. From selecting space-saving fixtures that seamlessly merge form and function to the strategic use of colors and materials that amplify the sense of upscale custom design work, we seized our chance to create an intimate retreat that defies its dimensions. Here is the story of building our half bath from scratch.

Adding a bathroom to your home is not just about convenience; it's a significant investment that can enhance your daily life and property value.

1. Initial Assessment

Take a close look at your home's layout. Consider factors like traffic flow, existing plumbing, and structural integrity. This assessment will provide crucial insights into the potential locations for your new bathroom.

2. Determine Need and Function

Define the purpose of your new bathroom. Is it for guests, family members, or as an ensuite to a bedroom? The function will influence its size, fixtures, and design. Here is a quick reference for general guidelines and considerations, and specific requirements may vary based on individual preferences and space availability.


Powder Room

Guest Bath

Family Bath



Minimum 2'x5'

Standard 5'x8'

Standard 5'x8'

Larger 8'x10'


  • Toilet

Compact, wall-mounted




  • Sink

Pedestal or wall-mounted

Vanity with storage

Vanity with Storage

Double vanity

  • Shower/Bathtub


Shower or bathtub

Shower and/or bathtub

Separate tub and shower

Design Considerations

  • Color Scheme

Elegant and inviting

Coordinated with decor

Family friendly

Coordinated with decor

  • Lighting

Well lit, decorative

Task lighting and ambient

Task lighting and ambient

Task lighting and ambient

  • Flooring

Easy to clean, non-slip

Durable and easy to clean

Durable and easy to clean

Coordinated with decor

  • Storage

Minimal storage

Adequate storage

Adequate storage

Ample storage

  • Mirrors

Decorative mirror

Medicine cabinet or mirror

Medicine cabinet or mirror

Double medicine cabinets or mirrors

  • Towel Storage

Towel hooks or rack

Towel bars and shelves

Towel bars and shelves

Towel bars and shelves

  • Accessibility

Basic amenities

Child friendly

Child friendly

Connected to primary bedroom

3. Local Regulations and Building Codes

When starting a residential bathroom project in the United States, you should reference and comply with various building codes and regulations to ensure that your project meets safety and structural standards. The specific codes you need to follow may vary depending on your location, as building codes are typically adopted and enforced at the local or state level. However, some commonly referenced building codes and standards for residential bathroom projects include:

  1. International Residential Code (IRC): The IRC provides comprehensive guidelines for the construction of single-family and two-family dwellings, including residential bathrooms. It covers aspects such as framing, plumbing, electrical, ventilation, and accessibility.

  2. International Plumbing Code (IPC): The IPC addresses plumbing-related aspects of residential bathrooms, including water supply, drainage, venting, and fixture installation. It provides standards for pipe sizing, fixture placement, and other plumbing considerations.

  3. International Mechanical Code (IMC): The IMC deals with mechanical systems in residential buildings, including ventilation and exhaust requirements for bathrooms. It provides guidelines for maintaining indoor air quality and preventing moisture-related issues.

  4. National Electrical Code (NEC): The NEC outlines electrical safety standards for residential and commercial buildings. It includes requirements for wiring, outlets, switches, and lighting fixtures in bathrooms to ensure electrical safety.

  5. Accessibility Codes: Depending on the location and type of project, you may need to follow accessibility standards such as the Americans with Disabilities Act (ADA) or local accessibility codes. These codes dictate specifications for accessible bathroom design, including grab bars, clearances, and fixtures for individuals with disabilities.

  6. Local Building Codes: Municipalities and states may have their own building codes and regulations that you must follow. These codes can vary significantly from one jurisdiction to another, so it's essential to check with your local building department for specific requirements.

  7. Energy Codes: Some areas have energy codes that dictate energy-efficient design and construction practices, including requirements for insulation, lighting, and ventilation. Compliance with energy codes can impact the design and materials used in the bathroom project.

  8. Fire Codes: If your bathroom project involves changes to the building's fire protection systems, you may need to comply with local fire codes. This can include requirements for fire-rated walls, doors, and sprinkler systems.

  9. Health Department Regulations: In some cases, you may need to comply with health department regulations related to sanitation and wastewater disposal, especially if you're making changes to the plumbing system.

It's crucial to consult with your local building department or code enforcement agency before starting any residential bathroom project. They can provide you with the most up-to-date information on applicable codes, permits, and inspections specific to your location. Additionally, consider consulting with a licensed architect or contractor who is familiar with local building codes to ensure your project is in compliance with all relevant regulations.

4. Budget and Design

Collaborate with an architect to design the layout, fixtures, and finishes that align with your budget and preferences. Establish a clear design plan before moving forward.

5. Location Consideration

Choosing the right location is pivotal. Consider these factors:

  • Proximity to existing plumbing: Minimize costs by locating the bathroom near existing water and sewer lines.

  • Traffic flow: Opt for a location that doesn't disrupt the natural flow of your home.

  • Utilize underutilized spaces: Convert closets, corners, or unused areas into functional bathrooms without altering your home's footprint.

6. Structural Considerations

Work with a structural engineer if necessary to assess the structural modifications needed for the new bathroom. Reinforce walls or floors as required.

7. Plumbing and Electrical

Plan the plumbing and electrical layout. Collaborate with experts to ensure seamless integration with your existing systems.

8. Obtain Permits

Secure the necessary building permits and approvals before commencing construction. Compliance with regulations is essential.

9. Construction

Construct the framework, walls, and partitions. Install plumbing lines, electrical wiring, and insulation before closing walls.

10. Fixture Installation

Position and install fixtures such as toilets, sinks, showers, and bathtubs according to your design plan.

11. Finishing Touches

Select flooring materials, paint, tiles, and accessories that complete the look. Ensure the space aligns with your envisioned design.

12. Enjoy the New Space

Test all fixtures, plumbing, and electrical systems. Once everything is verified and approved, enjoy the convenience and comfort of your new bathroom.


Adding a bathroom to your home is a transformative process that requires careful planning, collaboration with professionals, and adherence to regulations. As an architect, my goal is to help you navigate this journey seamlessly, ensuring that your new bathroom not only meets your needs but also enhances your home's functionality and value. With the right guidance and approach, your dream bathroom is within reach.


bottom of page