7 Common ADU Design Mistakes and How to Avoid Them

7 Home Additions That Can Add Value to Your Property

According to research, ADUs have become increasingly common over the past decade. Currently, there are 1.4 million single-family homes with ADUs in the US, a number that grew by 8% year over year from 2009 to 2019. They’ve also grown as part of the rental market, with listings growing from 1.8% to 4.1% within the same period.


As more and more people are looking to create accessory dwelling units, it’s important to be aware of the common ADU design mistakes that can be made during the design process. By avoiding these mistakes, you’ll make the process much smoother and ensure that your ADU is both safe and functional.


In this article, we’ll discuss eight of the most common ADU design mistakes and how to avoid them. Let’s get started!


1. Hiring an Inexperienced or Unlicensed Contractor

The construction of an ADU is a major investment. You want to ensure that the ADU building service is experienced, licensed, and insured. Inexperienced contractors may cut corners to save on costs, resulting in subpar workmanship.

This could lead to issues down the road, such as electrical problems or faulty plumbing. Unlicensed contractors also pose a risk as they may not be up to date on the latest building code requirements.

It’s essential to do your research when hiring a contractor and to make sure they’re qualified to build an ADU. Check their reviews and referrals from past clients to gauge whether they have worthy ADU design ideas and level of customer service.


2. Improper Kitchen Measurements

One of the most common ADU design mistakes we see people make is not properly measuring their kitchen. You’d be surprised at how much space appliances such as your fridge, oven, and dishwasher can take up.

When planning the kitchen layout, take into account the measurements of your appliances. You’ll also want to leave enough space for people to walk around comfortably. A professional ADU designer will be able to help you create a functional and comfortable kitchen layout.


3. Few Windows or Poor Window Placement

Windows are an important part of the design, so take the time to think about their placement. You’ll be glad you did when you’re not dealing with a stuffy, cramped ADU.


Not only do windows let in natural light, but they also help with ventilation. If you have too few windows or place them in the wrong spot, you could end up with an ADU that’s stuffy and difficult to keep cool.

Think about the sun’s orientation when placing your windows and try to avoid any areas that will get direct sunlight for most of the day.


Another common mistake is not having egress windows in the unit. Egress windows are required by code in most states, so check your local ADU regulations before finalizing your window placement.


4. Not Soundproofing the Unit

Whether its footsteps thumping overhead or cabinets slamming in the kitchen, it can be incredibly frustrating (and disruptive) to constantly be jolted out of your sleep or concentration by noise from the unit above.

Soundproofing isn’t just for Hollywood celebrities anymore. With a few strategic additions, you can make your ADU as quiet as possible. Here are a few things you can do to soundproof your unit:

  • Add insulation to the walls
  • Install double-pane windows
  • Use acoustic caulk around doors and windows
  • Add a layer of drywall
  • Install a solid core door

By taking the time to soundproof your unit, you’ll not only make your tenants happy, but you’ll also be protecting your investment.


5. Hiring an Inexperienced ADU Designer

The design process for an ADU is different from a typical home addition or even a new build. There are unique code requirements and regulations that need to be taken into account from day one.

An inexperienced designer might not know about these requirements, which could lead to costly delays and changes down the road.

They might also not be aware of the latest trends in accessory dwelling unit design. You want someone who can help you create a modern and stylish unit that will be appealing to renters.

When you’re looking for an ADU designer, ask about their experience with these types of units. You should also ask to see examples of their previous work and check their track record.


6. Making Changes During Construction

This one might seem like a no-brainer, but you’d be surprised how often people change their minds about things during construction. Maybe you walk by the site and decide the front door needs to be on the other side or that you want larger windows.

It’s important to remember that making changes during construction will add both time and money to the project. The general contractor will need to halt construction, order new materials, and make the changes you’ve requested.

All of this takes time which lengthens the build process and subsequently raises the price. It’s best to have a clear vision for your ADU before construction begins so there are no costly delays.


7. Not Incorporating Universal Design Principles

When designing an ADU, it’s important to keep in mind that not everyone who might want to live there now or in the future will be able-bodied.

According to the National Association of Home Builders, by 2050, almost 90 million of the U.S. population will be over 65 years old. And as we age, we often face mobility challenges.

While some might think of accessibility only in terms of wheelchair users, there is a much broader spectrum to consider. For example, someone who is aging might have difficulty climbing stairs or getting in and out of a bathtub.

By incorporating universal design principles into your ADU design, you can make your unit accessible and livable for a wider range of people.

Some features to consider incorporating are:

  • Wider doorways and hallways
  • Lever door handles
  • Grab bars in the bathroom
  • Ramped entryway
  • No-step entryway

Incorporating these features will make your ADU more accessible, not just for people with mobility challenges but for anyone who might have difficulty using stairs or narrow doorways.


A Guide to Costly ADU Design Mistakes

Building an ADU can be a great way to add value to your property and create rental income. But it’s crucial to avoid making common ADU design mistakes that can delay the construction process and increase the cost. By following these ADU design tips, you can build the ADU of your dreams without any headaches.


If you need help designing or building your ADU, our team can assist you. We have experience designing and building these units and can help you navigate the process from start to finish. Contact us today for a quote.


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