The two car garage is the most popular way to create an ADU. The planning stage of an ADU garage conversion is crucial.

It can make or break your budget.

Careful planning can save you a lot of money, headaches, time, and probably some gray hair.

This guide will help sort through all the planning parts of your two car garage adu conversion.

Let’s dive into the steps to make your conversion a success!

Disclosure: This post may contain affiliate links, meaning I can earn commissions. If you decide to purchase through my links, it is at no cost to you.

Why Some Are Tackling the 2 Car Garage ADU Conversion Project

Converting a garage into an ADU (Accessory Dwelling Unit) is a great way to:

  • add living space
  • earn rental income
  • Help create affordable housing
  • provide a separate home for family members
Villa-The-H450 prefab adu kitchen

The JADU vs ADU: What is the difference?

In some areas, a garage conversion is called a Junior ADU (JADU).

The main difference is that a JADU is typically smaller (up to 500 sq ft) and must be part of the existing home, while an ADU can be a separate structure.


There could be some other nuances between the two like if utilities need to be separated or not from the primary home.

Not having to separate the water and sewer for your Garage Conversion could be a HUGE COST SAVINGS!

ADU Zoning, Permits, Codes, and Regulations

The First Step: Please make sure you can actually convert your garage into an ADU.

  • You may need to check the zoning of your property.
  • You can visit your local government website or call the Planning and Zoning Department.

The Second Step: Checking local regulations for your conversion project.

  • Visit your local building department to determine if you need a permit.
  • Ensure your plans meet local building codes to avoid any legal issues and ensure safety.

The Third Step: If your property is part of a Homeowners Association (HOA), verify whether the HOA rules.

  • Check to make sure your HOA allows the garage to be used for something other than parking.
  • Obtain necessary approvals from the HOA before starting your project.

2 Car Garage ADU Conversion Planning Considerations

  • Start by assessing the current state of the garage. Will you use the entire space or just part of the space?
  • Some garages have storage closets that might be utilized for the ADU.
  • Identify existing electrical outlets and note their locations.
  • Check for existing windows and determine if additional windows are needed.
  • Determine the number of breakers in the garage and assess if more breakers are needed.

What to Consider in a 2-Car ADU Garage Conversion Layout

Check the foundation, walls, and roof to ensure they can support the new living space. You may need to reinforce these areas to meet building codes and ensure safety.

The two biggest pieces in an ADU layout are the kitchen and bathroom.

When you locate the kitchen and bathroom next to each other in an ADU conversion, you can save on plumbing costs. Less pipe = less money.

Determine where water enters the house and plan how the new ADU will connect to the main home.

Choose a location for the kitchen and bathroom with easy access to plumbing. Most add the kitchen and bathroom to an outside wall for easier access.

AreaSuggested PlacementWhy
KitchenNear existing plumbing (e.g., back wall)Saves money on plumbing costs.
BathroomClose to existing plumbing linesKeeps utilities close, reducing installation costs.
Living/SleepingNear where the garage door wasEasy to add windows and frame up the new wall.

Example ADU Layouts for a 2 car Garage adu conversion

After you decide where the kitchen and bathroom will go, the remaining space for living, eating, and sleeping areas.

Some choose to have a private bedroom in the ADU and others do more of a studio setup where the bedroom is open to the entire room.

Here are some great 2 car garage adu layouts under 500 square feet.

What To Do With the Garage Door in an ADU Garage Conversion

When converting a garage into an ADU, handling the garage door is a significant structural consideration.

You can either remove the garage door entirely and replace it with a new wall and entrance or repurpose it to serve a different function.

Man Wearing Hat in Front of Entrance to a Garage

If you choose to remove the garage door, make sure to install a proper entry door to provide secure access to the ADU.

Most choose to frame in the garage door space. A lot of ADU conversions I have seen place the sleeping and living areas on the wall where the garage was as those spaces will have larger windows.

ADU Access to the Main House

Semi Open White Wooden Door

Access to the main house is another important aspect.

Most already have a door to their garage. Some may want to change the door if it happens to have a window.

Ensure this connection provides privacy and security for both the main house and the new unit.

Electrical Utilities for JADU Garage Conversion

Electrical panel finished

Upgrading the electrical system is often necessary when converting a garage into an ADU.

You may need to hire a licensed electrician to handle these upgrades safely.

Ensure you have enough outlets and that the wiring meets the demands of your new living space.

Assess the existing electrical breakers and determine if additional breakers are needed to support the new appliances and lighting.

Plumbing Utilities for JADU Garage Conversion

under the sink, that's where they hide (IMG_6569)

Plumbing is another critical aspect. Some ADU conversions require separate utilities. Plan how the new ADU will connect to the main water supply and sewage system.

It’s essential to place the kitchen and bathroom near existing plumbing lines to minimize costs and simplify installation.

Installing pipes for the kitchen and bathroom can be complex, especially if your garage is detached from the main house.

Ensure proper drainage and consider hiring a professional plumber to complete this part of the project.

ADU Climate Control and Comfort

air conditioner, air conditioning unit, hvac

Insulating the walls and ceiling will help maintain a comfortable temperature and improve energy efficiency.

To make the ADU comfortable year-round, adding an air conditioning system is essential. Most say it is vital in the South. I agree.

You can choose between central air, mini-split systems, or portable units based on your needs and budget. It is likely you will want to add a separate unit for the ADU.

Most main homes already have a unit installed that can only handle the main house. Adding more living footage to cool it could cause strain on the main unit and cause it to fail.

Heating options should also be considered to keep the space warm during colder months.

tiny house heating safety

Soundproofing and Privacy for your ADU Garage Conversion

Adding soundproofing materials to the walls and ceiling can create a more private and comfortable living environment.

This is especially important if the ADU is connected to the main house or if neighbors are close by.

Sound Proofing Goes In

Consider using soundproof drywall, acoustic panels, or insulation designed for noise reduction.

Ensuring privacy from the main house and neighbors will enhance the living experience for occupants of the ADU.

Sustainability Considerations when converting a garage into an ADU

Using eco-friendly materials and incorporating energy-efficient appliances and fixtures can make your ADU more sustainable.

solar panels, renewable energy, photovoltaic cells

Look for materials with low environmental impact and consider options like solar panels or energy-efficient HVAC systems to reduce the carbon footprint of your new living space.

Installing energy-efficient windows and insulation can also contribute to lower energy costs and a more environmentally friendly home.

A $58,000 2 car garage ADU Conversion in Panama City, Florida

Stephen LaChance converted their 2-car 400 sq ft garage into a cozy one-bedroom ADU. The ADU shared utilities with the main house.

They encountered a few challenges that increased the cost but resolved it by consulting a local expert.

The entire project took 3 months and cost around $58,000. His unit can be rented for $1,200 per month.

The budget for the build fell right in line with the estimated averages.

Planning for a 10%-20% cushion is wise in any renovation or building project.

Accessory Dwelling Unit Budget Considerations

Budgeting is a crucial part of any conversion project. Here’s a rough breakdown of potential ADU costs:

  • Electrical Upgrades: $2,000 – $5,000
  • Plumbing: $3,000 – $8,000
  • Insulation: $1,500 – $3,500
  • HVAC System: $2,000 – $6,000
  • Interior Finishes (flooring, paint): $5,000 – $10,000

To save money, consider doing some of the work yourself, like painting or installing flooring.

Also, shop around for materials and get multiple quotes from contractors.

Common Mistakes to Avoid with Garage Conversions

Avoid these common pitfalls:

  • Skipping the permit process: Always check local regulations.
  • Underestimating costs: Plan for unexpected expenses.
  • Poor insulation: Proper insulation is key to comfort and energy efficiency.
ADU Garage Conversion Checklist

Final Thoughts

The 2 Car Garage ADU Conversion is the most popular project that can provide additional living space, rental income, or a comfortable home for family members.

By following these steps and carefully planning each aspect of the conversion, you can create a beautiful and functional ADU.

Start planning your project today and enjoy the benefits of your new living space.

Frequently Asked Questions

Can I complete a garage conversion into a living space?

Check with your local zoning department and HOA to ensure you can make this change.

how much is a garage conversion?

A DIY garage conversion could be as low as $20,000. A conversion by a professional could be $40,000-$75,000.

how long does a garage conversion take?

Expect the project to take 3-9 months depending on the permit process.

will a garage conversion devalue my house?

Consulting a real estate agent or appraiser to be sure. Typically, ADUs add value.

  • Erin Hybart

    Meet Erin, a real estate enthusiast with a wealth of knowledge and an insatiable curiosity for all things Real Estate and living with intention. She passionately advocates for alternative, affordable, and eco-friendly housing solutions. She believes in pushing the industry's innovation boundaries and thinking outside the box. As a licensed real estate agent in Louisiana, Erin dedicates herself to assisting clients in buying and selling properties and mentoring fellow agents to succeed in their own Real Estate businesses. In addition to her professional pursuits, Erin channels her expertise into captivating house-flipping adventures.

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