Buying ADU plans is the exciting part — and the step where the most expensive mistakes happen. Run this checklist first.
1. Confirm your jurisdiction allows the project
Plans are buildable on paper, but your city decides what is buildable on your lot. Size caps, setbacks, parking, and design review rules vary block by block. A free feasibility assessment or a $349 Engineer Review settles this before money changes hands.
2. Check the plan fits your property
Square footage, lot coverage, and setbacks decide whether a plan can be placed on your lot as designed. A 750 sq ft two-bedroom plan may be perfect on paper and illegal on a small or oddly shaped parcel. Also check utility locations — the plan needs to connect to reality.
3. Know what your permit office requires
Most jurisdictions require professionally prepared construction drawings, and many require structural engineering sealed by a licensed Professional Engineer (PE stamps) for ADUs. Ask (or have your plan provider check) what submission depth your city requires: concept designs cannot be permitted.
4. Understand what the package actually includes
Plan products are a ladder, not one product:
- Concept packages — for visualizing the design and testing the idea. Not permit submittable.
- Permit-ready drawings — complete construction documents prepared for permit submission.
- PE-stamped engineering — structural (and where required, other) disciplines sealed by a licensed engineer, required by many jurisdictions for ADU permits.
- Complete permit packages — drawings plus engineering plus permit-handling support, the full path to an issued permit.
Buying a cheaper package that cannot pass your permit review is the most expensive way to save money.
5. Clarify how the plan gets finalized for you
Every property is slightly different. When you select a plan with QuiPlans, the purchase starts a kickoff meeting where an engineer reviews your property specifics and finalizes or adjusts the plan for your lot before delivery — so the drawings you receive are yours, not just the catalog's.
The short version
Feasibility first, fit second, requirements third, package type fourth. Get those right and the purchase itself is the easy part.
