From Dirt to Done, Your ADU Starts Here
Adding an Accessory Dwelling Unit to your property has never been easier.

Benefits of an Accessory Dwelling Unit (ADU)
An ADU is a small, independent residential unit built on the same lot as a main residence. Here’s why they’re skyrocketing in popularity!
Increase your home's value
Average increase of 35% according to National Association of Realtors, 2023
Generate revenue through your ADU
Earn passive rental income without the need to leave your primary residence.
Provide space for extended family
Statistics show more people are building ADUs to help ease the strain on finances and families.
How It Works
From Vision to Reality in 4 Simple Steps
1. Consultation
Contact us for a free consultation, feasibility assessment, and estimate via phone.
2. Site Preparation
Our team handles the excavation and groundwork, to prep your site for construction.
3. Construction
FtS will facilitate construction, or we can work with your existing General Contractor.
4. Completion
Your ADU is ready for use—whether as extra living space, rental income, or a cozy family retreat.
Book a Free Consultation
Request a 15 minute phone call with our team to take the next step in building your ADU.
Frequently Asked Questions
What is an ADU?
An ADU is an Additional (or Accessory) Dwelling Unit. They can either be attached to your current home or detached. Detached ADUs are also known as DADUs. Some people rent their ADUs out for additional income each month, or house their extended family.
What is the process to build an ADU?
First, a feasibility study is done to see if you can get permits to build an ADU. It has become much easier to get permitting with recent changes to Washington State zoning laws. Then you will need to research what you want, design, finance, permit, and then BUILD! FtS Excavation has built a great project management team to help their ADU customers with any of these steps.
What is the cost for site preparation of the ADU?
The site work of any construction project is one of the biggest unknown variables. As you may suspect, this is a complicated question and the answer depends a lot on where the ADU is being built and what is required for permitting. The best-case scenario would be around $8,000, for simply digging out a small foundation. A good rule of thumb to budget is 30% of the total build cost. Remember it could be much less, or much more than that. Call us for a free estimate. Our experts can tell you what will likely be required for your site development.
I want to build an ADU. What do I need to do first?
Spend some time researching styles and ideas for what you want to build. Once you have an idea of what you want and how much it will cost, you will want to do a basic feasibility study. Then decide if you want to hire a general contractor to build the ADU, or if you want to be the general contractor and hire the subcontractors yourself. We are happy to give you a free estimate and resources to help with your project either way.
Who do you recommend as a general contractor?
We partner with several builders, whom we have vetted. As you may know, general contractors can be very professional or very shady. In order to protect our customers and our reputation, we are very careful about who we choose to build with. Please call our office for a free estimate to Dig That ADU, and we can discuss assigning one of our project managers to your project who will provide an extra layer of oversight for free and ensure that your ADU is done under budget and under time.
How do we get permits?
Your builder will be responsible for working with your local municipality to get permits on your behalf. Permit costs will be included in your budget. If you choose to act as your own general contractor, you will be responsible for obtaining your own permits. We have found that local municipalities can be very helpful, although permitting can be a lengthy process. Allow for 6 months to a year for permits.
Can I build an ADU on my property?
That is a great question and will be answered before signing a contract with your builder. The biggest factor for feasibility will be the site preparation requirements. Call us for a free estimate and we can help you do a basic feasibility study as well as point out some costs in your site development that will need to be considered in your budget.
Can I sell my ADU after I build it?
Actually, you can even sell it before you build it. It’s called condominiumization, or condominiuming. Say that five times fast. It can be done to any property! We think that it is very affordable, can be done very quickly and is a much better solution than subdividing. We don’t provide this service in-house, but we do have business associates who do. It is a niche and needs to be done by an attorney who specializes in it. Call us for more information.
What is your territory?
We serve the South Puget Sound from Olympia up to Bremerton, all of Pierce County, and into King County. We are a growing company, so our territory is also expanding.

Meet Your ADU Experts:
FtS Excavation
Our excavation expertise lays the foundation for a smooth ADU build, making FtS your one-stop solution. With deep knowledge of the entire process, we’re here to guide you every step of the way—from initial planning to final completion.