Understand the existing space
An attached ADU or conversion starts with the structure already in place. Review access, ceiling heights, existing systems and the relationship to the main home before committing to a layout.
Make room within the home you have.
Explore an attached accessory dwelling unit or a conversion shaped around your existing home, priorities and property.
Melissa Cook
★★★★★
We absolutely love our home. The team were so great. We did have some issues. But what sets Justin apart is that he cared.
Edwin Robbins
★★★★★
Justin and Danielle were very responsive and did a great job keeping me informed throughout the process: from timeline, to selecting finishes and ongoing progress.
Devon Hjelm
★★★★★
His design team is great and we were able to arrive at a look that matched our vision. Communicative and organized. Would definitely recommend.
Elaine and John Karstens
★★★★★
We had a master bath makeover. TimberworX was able to craft a design that met both our desires and our budget.
Julian Duffy
★★★★★
They delivered everything we wanted and more, kept on schedule and budget, and almost 3 years on from the work we love our new spaces, and Justin is still happy to take a call here and there if we're in need of advice.
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ADUs & conversions by TimberworX
Give the space independence
Plan a practical entrance, kitchen, bathroom, storage and privacy. Design and construction need to work together so the space feels considered.
Compare attached and detached
A DADU creates a separate building; an attached unit or conversion works within or beside the main structure. The right path depends on site conditions, project goals and local review.
Hear from our customers
Melissa Cook
★★★★★
“We absolutely love our home. The team were so great. We did have some issues. But what sets Justin apart is that he cared.”
Edwin Robbins
★★★★★
“Justin and Danielle were very responsive and did a great job keeping me informed throughout the process: from timeline, to selecting finishes and ongoing progress.”
Devon Hjelm
★★★★★
“His design team is great and we were able to arrive at a look that matched our vision. Communicative and organized. Would definitely recommend.”
Elaine and John Karstens
★★★★★
“We had a master bath makeover. TimberworX was able to craft a design that met both our desires and our budget.”
Julian Duffy
★★★★★
“They delivered everything we wanted and more, kept on schedule and budget, and almost 3 years on from the work we love our new spaces, and Justin is still happy to take a call here and there if we're in need of advice.”
A few things to know
What is a DADU?
A detached accessory dwelling unit is a self-contained home on the same property as a principal dwelling, in a separate building. People also call them backyard cottages.
Can I build one on my property?
That starts with the specific parcel and its jurisdiction. Zoning, site access, utilities, setbacks and other property conditions need review. Washington’s ADU planning overview is a starting point; the permitting authority determines the requirements for your project.
How much does a DADU cost?
There is no useful universal price for every property. Design, site work, utilities, engineering, permits and finishes all shape the budget. TimberworX offers ballpark estimates for qualified projects; detailed budgeting is a paid preconstruction service.
Can you help with design and permits?
Yes. TimberworX provides design-build support, preconstruction planning, permitting and construction management. The documents and review path depend on location and scope.
How long will it take?
Design, local review, site work and construction all affect timing. Establish the schedule for the actual property and scope before treating any timeline as a commitment.