How Long Does it Take to Build an ADU in Colorado?

The short answer: 9-18 months.

This includes all phases, from design and permitting to construction and final inspection. While every project is unique, understanding the steps involved can help you set realistic expectations.

Read on to learn more about the process of building an ADU. We’ll break down the various stages of building an ADU in Colorado, explore potential delays, and provide insider tips to help you stay on track.

How Long Does It Take to Design an ADU?

The design phase is where your vision comes to life. This process usually takes 2 to 3 months, depending on the complexity of your ADU and your preferences.

Key Steps in the Design Process:

1. Initial Consultation: Discuss your goals, budget, and site requirements with your builder.
2. Site Feasibility Study: Evaluate your property’s potential, including zoning laws and utility access.
3. Drafting Plans: Work with an architect to create preliminary designs.
4. Revisions and Approvals: Adjust the plans based on your feedback and prepare for permit submission.

At Kindred Tiny Homes, we offer customizable pre-approved designs to accelerate this phase, saving you time and money.

How Long Does It Take to Get an ADU Permit?

Permitting is often the most time-consuming step, taking anywhere from 3 to 9 months. The duration depends on your location, the complexity of your project, and the responsiveness of your local building department.

Steps in the Permitting Process:

1. Application Submission: Submit plans, site surveys, and other required documents to your local building department.
2. Plan Review: The city reviews your plans for compliance with zoning, safety, and building codes.
3. Revisions: If the city requests changes, you’ll need to revise and resubmit the plans.
4. Approval: Once approved, you’ll receive your building permit and can proceed to construction.

ADU Permitting Times by City in Colorado

Here’s a look at estimated permitting times in key Colorado cities:

City ------------ Total Permitting Time ------- Plan Check Round 1 Time

Denver ------------- 3-9 months ------------------ 6-8 weeks

Boulder ------------- 3-7 months ------------------ 5-7 weeks

Fort Collins --------- 3-6 months ------------------ 4-6 weeks

Golden ------------- 4-6 months ------------------ 4-5 weeks

Douglas County ---- 3-5 months ------------------ 3-4 weeks

Note: Times vary based on the complexity of the project and staff availability at the city planning office.

How Long Does It Take for the Construction of an ADU?

The construction phase typically lasts 4 to 6 months. This timeline depends on the size, type, and complexity of the ADU, as well as factors like weather and material availability.

Steps in the Construction Process:

1. Site Preparation: Clearing and grading the land, installing utilities, and laying the foundation.
2. Framing and Roofing: Building the structure of the ADU.
3. Systems Installation: Adding plumbing, electrical, and HVAC systems.
4. Interior Finishes: Installing flooring, cabinetry, and appliances.
5. Final Inspections: Ensuring the ADU meets all safety and building codes.

At Kindred Tiny Homes, we prioritize efficiency and quality, keeping homeowners informed with regular updates throughout the build. Our average construction time is typically less than the industry, usually lasting around 12-18 weeks. 

7 Common Delays to Avoid in Your ADU Build

While every project faces unique challenges, the following issues are common culprits for delays. Here’s how to mitigate them:

1. City Delays

Permitting backlogs and lengthy plan reviews can stall progress. Avoid delays by submitting complete, accurate applications and working with a builder experienced in navigating local requirements.

2. Coastal Zone Regulations

While this is less relevant in Colorado than in coastal states, properties near sensitive ecological areas or flood zones may face additional environmental reviews. Be proactive by consulting local zoning maps early.

3. HOA Restrictions

Homeowners Associations (HOAs) may have specific rules about ADU construction. Review your HOA’s bylaws before starting your project and communicate openly with the board to address concerns.

4. Utility Upgrades

Some ADUs require utility upgrades, such as increasing water or electrical capacity. Coordinate with utility companies early to prevent last-minute surprises.

5. Right-of-Way Work

If your project involves work on public land, such as sidewalks or streets, you’ll need additional permits and approvals. Plan for these extra steps in your timeline.

6. Plan Revisions and Changes

Revisions are a normal part of the permitting process, but excessive changes can cause significant delays. Work with an experienced architect to minimize revisions by submitting thorough, compliant plans.

Why Do Plans Take Multiple Rounds of Revisions?

Plan revisions are often due to:

• Incomplete or unclear drawings.
• Changes in project scope after submission.
• Feedback from multiple city departments.

While revisions can be frustrating, they ensure your ADU meets all safety and zoning requirements.

7. Material Lead Times

Global supply chain disruptions have increased lead times for certain materials, such as windows and appliances. Avoid delays by ordering materials early and choosing readily available options when possible.

Insider Tips for Staying on Schedule

1. Choose a One-Stop-Shop Builder: At Kindred Tiny Homes, we handle every step of the process, reducing coordination delays.
2. Start Early: Begin the design and permitting process as soon as possible to account for potential roadblocks.
3. Communicate Clearly: Stay in regular contact with your builder and city officials to address issues promptly.
4. Be Flexible: Adjust expectations for timelines when facing unavoidable delays, such as severe weather.

Conclusion

Building an ADU in Colorado is a rewarding investment, but it requires careful planning and patience. By understanding the timeline and potential delays, you can set realistic expectations and ensure a smoother process.

At Kindred Tiny Homes, we’re committed to making your ADU journey as seamless as possible. From design and permitting to construction and final walkthroughs, our team handles every detail with professionalism and transparency. Contact us today to get started on your ADU

‍