ADU builders
ADU designer: what a drafter delivers
By the HyreADU research desk. Last checked .
The short answer
An ADU designer, sometimes called a drafter, prepares the drawings your city reviews and your builder prices. In California an unlicensed designer may draw a conventional wood-frame ADU of up to two stories (Bus. & Prof. Code § 5537). The work you are buying is a permit-ready set, not a pretty floor plan.
What a permit set includes
A typical ADU set has a site plan with setbacks and utility routes, floor plans, elevations, sections, a roof plan, electrical and plumbing layouts, and energy compliance forms. Your city’s ADU checklist lists what it needs. Ask your designer to work from that checklist.
Where a designer stops
If the design steps outside conventional wood framing, the building official must require stamped plans or calculations for that part from a licensed engineer or architect. Hillside foundations, long beams and second stories over garages often need a structural engineer. Energy forms are often prepared by a Title 24 consultant.
What to ask before hiring
How many ADU permit sets have you taken through this city? Does your fee include plan check corrections? Who prepares the energy forms and the structural calculations? Will I own the drawings so I can bid them to several builders?
Drawings in hand let you get competing bids. That is the best cost control you have.
What to do next: read the questions to ask an ADU builder, check what decides ADU cost, then tell us about your project. Matching is not live yet, so we reply with information, not a quote.
Get ADU optionsQuestions
Is an ADU designer licensed?
Not necessarily. California exempts conventional wood-frame houses from the architect license rule.
Can a designer use a preapproved plan?
Yes, and many cities publish them. Check whether a modified plan still counts as preapproved in your city.
Do I need a survey first?
Often the site plan needs accurate lot lines. See land survey for an ADU.
Does HyreADU design ADUs?
No. HyreADU is a publisher and designs nothing.
Sources
- Bus. & Prof. Code § 5537 (plans exempt from architect licensing). Checked October 27, 2026.
- California Energy Commission, 2025 Building Energy Efficiency Standards. Checked September 5, 2026.
- Gov. Code § 65852.27 (preapproved ADU plans). Checked September 5, 2026.
HyreADU is a publisher. It does not design, permit or build ADUs, has no partner builders, and gives no legal, tax or engineering advice. Rules vary by state and city; California rules are labeled as such.