Top 5 Mistakes Homeowners Make When Building an ADU in Central Oregon

Accessory Dwelling Units (ADUs) are becoming increasingly popular in Central Oregon. From Bend to Redmond and Sisters, homeowners are discovering the benefits of adding a flexible, self-contained living space to their property. Whether for multi-generational living, rental income, or home office space, ADUs offer tremendous value.

However, building an ADU isn’t without its pitfalls. Many homeowners make costly mistakes that can lead to delays, extra expenses, or regulatory headaches. Here are the top 5 mistakes to avoid when building an ADU in Central Oregon.

1. Skipping the Research on Local Regulations

Mistake: Many homeowners assume ADUs are allowed anywhere on their property without checking city rules.

Why it matters: Cities in Central Oregon—Bend, Redmond, Sisters, Sunriver—have specific rules for ADU size, setbacks, parking, and occupancy. Failing to comply can result in fines, denied permits, or forced redesigns.

Tip: Always consult your city’s planning department and review zoning regulations before investing in an ADU. Hiring a local architect or contractor familiar with Central Oregon ADU codes can save time and stress.

2. Underestimating Costs

Mistake: Homeowners often budget too low, thinking an ADU will be a small or inexpensive project.

Why it matters: The cost of building an ADU in Central Oregon can range from $150,000 to $300,000 or more, depending on size, materials, utilities, and permits. Hidden expenses like utility connections, site prep, and landscaping can add up quickly.

Tip: Create a realistic budget with a contingency for unexpected costs (10–20% of total). Work with local builders who have experience with Central Oregon ADU projects.

3. Ignoring Utility and Infrastructure Needs

Mistake: Failing to plan for plumbing, electricity, water, or sewer connections.

Why it matters: Improper planning can lead to expensive retrofits. Some ADUs require separate utility meters, while others can share existing connections.

Tip: Consult with utility providers and your contractor early in the planning stage to ensure smooth connections and code compliance.

4. Overlooking Design and Functionality

Mistake: Prioritizing aesthetics over functionality or failing to consider the lifestyle of future residents.

Why it matters: An ADU should meet the needs of its occupants. Poor layout, inadequate storage, or limited privacy can make a unit less comfortable and less marketable as a rental.

Tip: Consider who will live in the ADU (seniors, young adults, renters) and design with both privacy and livability in mind. Central Oregon’s scenic surroundings can also be leveraged with outdoor patios, decks, or views.

5. Not Planning for the Future

Mistake: Treating the ADU as a short-term project without considering long-term use or resale value.

Why it matters: ADUs can add significant property value and versatility. A poorly planned unit may limit future opportunities for rental income or multi-generational living.

Tip: Build with long-term flexibility in mind. Features like a separate entrance, energy-efficient systems, and high-quality finishes increase both comfort and resale value.

Building an ADU in Central Oregon can be a game-changer for multi-generational living, rental income, or flexible space. Avoiding these common mistakes—researching regulations, budgeting properly, planning utilities, prioritizing functionality, and thinking long-term—ensures your ADU is both valuable and enjoyable.

With the right planning and local expertise, your ADU can enhance your lifestyle, increase property value, and serve your family for years to come. Property’s assessed value — but it also boosts resale and rental potential significantly.

FAQs

1. How much does it cost to build an ADU in Central Oregon?

Most ADUs range from $150,000 to $300,000, depending on size, design, and materials. Custom designs or units with high-end finishes may cost more.

2. Do I need a permit to build an ADU?

Yes. Every city in Central Oregon—Bend, Redmond, Sisters, Sunriver—requires permits for ADU construction, including zoning approval, building permits, and sometimes utility permits.

3. Can I rent out my ADU?

Yes. ADUs can often be rented long-term or short-term, but local regulations vary. Check city ordinances for Bend, Redmond, or Sisters before renting.

4. How long does it take to build an ADU?

Construction typically takes 6–12 months, including design, permits, and site preparation. Prefabricated units may take less time.

5. Can an ADU increase my property value?

Yes. ADUs add versatility and appeal to buyers looking for multi-generational living or rental income potential.

6. Are ADUs suitable for multi-generational living?

Absolutely. ADUs provide privacy and independence while keeping family members close—ideal for aging parents or adult children.

7. Should I hire a local contractor for my ADU?

Yes. Local contractors are familiar with Central Oregon building codes, permitting requirements, and climate considerations, ensuring a smoother project.