what are accessory dwelling units 

An ADU is a small build with full-size decisions—site, utilities, comfort, and long-term use all matter. Before sketches get serious, map constraints: access for crews, utility tie-ins, drainage, and how the unit will sit for sunlight and privacy. These factors often drive cost more than square footage. Design decisions get simpler when you’re honest about daily routines—storage, privacy, and easy-clean surfaces usually win. If you’re comparing approaches, weigh detached vs. garage conversion vs. basement unit based on site access, utility distance, and how much disruption you can tolerate. For a clear overview and a sensible starting checklist, see: what qualifies as an adu in washington state. Good plans reduce rework; rework is where budgets quietly leak. A realistic schedule includes ordering lead times and inspection windows, not just a hopeful start date. When in doubt, simplify—fewer custom details often means faster progress and cleaner results. When in doubt, simplify—fewer custom details often means faster progress and cleaner results. A realistic schedule includes ordering lead times and inspection windows, not just a hopeful start date. When in doubt, simplify—fewer custom details often means faster progress and cleaner results.