Map Marker Icon  Serving Monroe, WA & the surrounding area
  Improving Homes • Improving Lives  

The Ultimate Guide to Building Your

Accessory Dwelling Unit (ADU)

home office remodeling icon


mother in law apartment icon


bedroom remodeling icon


kitchen upgrades icon


sheds and garages additions icon


interior home remodeling icon


Let's Get Started

"*" indicates required fields

Max. file size: 10 MB.

Are you looking for the additional living space or income of an ADU?

Love the home you live in but need more space? We get it. Families grow and needs change over time. Sometimes, your home has to grow and change with you. Perhaps the time has come to consider a mother-in-law apartment for aging loved ones, or maybe you're ready to increase your home's value and create a source of passive income with a rental unit.  Adding a secondary living space or accessory dwelling unit (ADU) to your property is a great solution but the idea can come with many questions. 


What is an Accessory Dwelling Unit?

An ADU is a smaller secondary dwelling unit that shares the building lot of a single-family residential home. ADUs go by many names – such as:

  • Attic apartment
  • Granny flat
  • Backyard cottage
  • Garage conversion
  • Basement apartment
  • Mother-in-law suite


What are the Qualifications of an ADU?

For a secondary dwelling unit to legally qualify as an ADU, there are a few features it must have:

  • It must have a foundation (can be its own foundation or a shared foundation with the primary house)
  • It must have legal access to water, sewer, and utilities.
  • It must have a fully functional living space – living room, kitchen, bathroom, and bedroom.
  • The square footage should not exceed 1200 sqft.



What Type of ADU is Best for Your Home?

Interior ADU – this is a fully functional apartment often built in the basement or the attic.


Attached ADU – this unit shares at least one wall with the primary residence.


Detached ADU (DADU): A freestanding independent living space – think backyard cottage.


If you're considering adding an Accessory Dwelling Unit to your property, our team at Verum Construction can walk you through the process from start to finish. We'll explore the many different options with you, help you understand the ins and outs of the ordinance and zoning laws, and make sure your project is designed and completed according to your specific needs and vision. Our Truth In Building Process ensures that every step of the way you'll know exactly what to expect so there are no surprises. Contact us today to get started on your new ADU.

The Verum Truth-in-Building Process Delivers a Great Client Experience and a Better Result

Home Improvement Contractor
  • A home to be proud of, inside and out
  • A headache-free home improvement experience
  • More "Let's stay home tonight!" and less "Do we have to stay home again?"
  • Quality craftsmanship that goes beyond "trendy"

Bringing Your ADU to Life Has Never Been Easier

contact icon for home improvement quote

Call, email, or fill out the form above to get started.

free home improvement project quote
Get On the calendar

Once we receive your information, we’ll reach out to you to schedule an in-home consultation and to clarify the project details further.

free home improvement consultation
On site consultation

We will meet and discuss your project and vision.