Room Addition Permit Requirements in Centennial, CO

Centennial is a city of 106,883 residents in Colorado that follows the 2018 IRC. Centennial's building department is stricter than the standard IRC on room addition work, expect fewer exemptions and more situations that require a permit. You're looking at roughly $270 – $900 in permit fees, plan on about 2 weeks for approval, plus you can apply online.

By Joey, Founder · Last verified March 29, 2026 · How we research →

Population: 106,883 Code: 2018 Verified: 2026-03-29 3 local rules

When you need a Addition permit in Centennial

Required·Rule 1

Room additions require a building permit.

Estimated Fee$270 – $900
Typical Timelineabout 2 weeks
SourceCity of Centennial Code / 2018 IRC
Required·Rule 2

Room additions over 200 sq ft require full plans.

Estimated Fee$450 – $2,700
Typical Timelineabout 4 weeks
SourceCity of Centennial Code / 2018 IRC
Required·Rule 3

Second-story additions require structural engineering.

Estimated Fee$720 – $4,500
Typical Timelineabout 5 weeks
SourceCity of Centennial Code / 2018 IRC

Room Addition Permit Costs: Centennial vs. Nearby

Centennial comes in on the low side for Colorado. You're looking at $270 – $4,500 here, compared to the state average of $460 – $2,310.

CityEstimated Fee
Centennial $270 – $4,500
Denver $400 – $5,000
Colorado Springs $300 – $5,000
Aurora $360 – $4,500

Fees shown are estimates based on local building code data. Actual fees may vary based on project scope and valuation. See all Centennial permit costs →

Zoning & HOA Considerations

Zoning

Room additions typically require zoning review for setbacks, height limits, and lot coverage. Your addition must comply with your zoning district's building envelope requirements.

HOA Communities

If you live in an HOA community: room additions almost always require HOA architectural review approval. HOAs may restrict the size, style, materials, and exterior appearance of additions to maintain neighborhood consistency.

Estimated Project Timeline in Centennial

Here's a typical timeline for a room addition project in Centennial, CO:

Week 1
Get quotes & finalize design
Contact licensed contractors, get 3+ quotes, finalize project scope and drawings (plan drawings required).
Week 2
Prepare permit documents
Contractor prepares site plan, construction drawings, and permit application. Gather required documents per your city's checklist.
Week 3
Submit permit application
Your contractor submits the application to Centennial's building department, apply online here.
Week 4-8
Plan review & approval
Typical processing time in Centennial: about 5 weeks. Plan review examiner checks drawings for code compliance.
Week 9+
Construction & inspections
Post the permit card on site. Work begins. Schedule inspections at required stages (varies by project). Final inspection required before closing the permit.

Timeline is based on Centennial's typical about 5 weeks permit processing time. Actual timelines vary by project complexity, completeness of application, and current department workload.

Need an Addition permit in Centennial, CO?

Answer a few quick questions for a personalized answer about your specific project.

Check Now, Free →

Building Department Contact

NameBuilding Division
Address13133 E. Arapahoe Rd., Centennial, CO 80112
HoursMon-Tue 8am-5pm; Wed 9am-5pm; Thu-Fri 8am-5pm

Frequently Asked Questions

Estimated permit fees for Room Addition projects in Centennial, CO range from $270 – $4,500. Fees vary based on project scope and valuation.

It depends on the specifics of your project. Some smaller Room Addition projects may be exempt from permit requirements, while larger ones typically require a permit. Use our free lookup tool to check your specific situation.

Working without a required permit in Centennial can result in fines, stop-work orders, being required to remove completed work, and complications when selling your home. It's always best to check first.

Typical approval time for Room Addition permits in Centennial is about 2 weeks. More complex projects may take longer if plan review is required.

If you live in an HOA community, you may need architectural review approval in addition to a building permit. HOA rules and city building codes are separate, you may need to satisfy both. Review your CC&Rs and submit to your HOA's architectural review committee before starting work.

Learn More About Room Addition Permits

Read our complete guide covering permit requirements, costs, common exemptions, and the application process.

Read Room Addition Guide →

Estimate your permit fees →

Disclaimer: This information was last verified on 2026-03-29. Building permit requirements may change. Zoning requirements (setbacks, lot coverage, height limits) are separate and vary by location. Always confirm with your local building and planning departments before starting your project. PermitMint provides general guidance, not legal advice.