Building permits in Arapahoe County, Colorado
Find the right authority before you build. Arapahoe County permitting follows Colorado law — here is exactly who issues the permit and where to start.
County + cities (mixed)
Arapahoe County — Public Works and Development (Building Division)
The Arapahoe County Building Division issues building permits only for unincorporated Arapahoe County. Inside incorporated municipalities — Aurora, Centennial, Littleton, Englewood, Sheridan, Greenwood Village, Cherry Hills Village — the city building department issues permits instead.
Open the official permit portal →
The county enforces the 2021 IBC/IRC (effective April 1, 2022) with amendments. Permits and inspections are handled through the county’s Accela Customer Access portal.
Permit cheat-sheet (Colorado rules)
| Project | Permit? | Authority | Typical fee | Timeline | Go / No-Go | Key notes |
|---|---|---|---|---|---|---|
| 🏠 Accessory Dwelling Unit (ADU) | Permit required | city | Valuation-based; set by the issuing city/county. | — | Case by case | Colorado is a home-rule state with no mandatory statewide residential code, so ADU rules vary by jurisdiction. Denver allows ADUs by right through its e-permits process; other cities/counties differ. When permitted by zoning, a full building permit is required. |
| 🪵 Deck / Porch | Conditional | city | Valuation-based; set by the issuing city/county. | — | Generally allowed | Some cities also require a permit for any deck attached to the house because of the structural connection. Mountain/WUI communities may require fire-resistant decking. Exempt: Most Colorado cities require a permit for decks >30 in above grade or >200 sq ft; ground-level decks below both are generally exempt. Denver and Colorado Springs follow IRC thresholds. |
| 🧱 Fence / Wall | Conditional | city | Usually no building permit for fences under 6–7 ft; zoning approval may be required. | — | Generally allowed | Front-yard and corner-lot fences have additional height/setback rules. Exempt: PPRBD exempts fences <7 ft (Colorado Springs requires zoning approval at ≥6 ft); Denver fences are generally permit-exempt under 6 ft. |
| 🛖 Shed / Outbuilding | Conditional | city | Valuation-based; set by the issuing city/county. | — | Generally allowed | Zoning setback and lot-coverage rules still apply. Exempt: PPRBD exempts detached accessory structures <200 sq ft (Colorado Springs zoning approval at ≥125 sq ft); IRC exempts ≤120 sq ft. |
| 🪜 Basement Finish | Permit required | city | Valuation-based; includes trade permits. | — | Generally allowed | Finishing a basement to living space requires framing, electrical, plumbing, and mechanical permits; bedrooms need egress windows. |
| 🚗 Garage / Carport | Permit required | city | Valuation-based; includes trade permits. | — | Generally allowed | New attached or detached garages require a full building permit and trade permits. |
| ☀️ Rooftop Solar PV | Permit required | city | Building + electrical permits; fee set by the city/county. | — | Generally allowed | Denver and many Colorado jurisdictions encourage solar; building + electrical permits required, with structural/snow-load review. |
| 🌡️ HVAC Replacement | Conditional | city | Mechanical permit; fee set by the city/county. | — | Generally allowed | Mountain/WUI communities may add fire-safety siting rules for equipment. |
| 🍳 Kitchen Remodel | Conditional | city | Valuation-based when structural, plumbing, or electrical work is included. | — | Generally allowed | Energy-code triggers apply to remodels. |
| 🛁 Bathroom Remodel | Conditional | city | Valuation-based when plumbing is relocated. | — | Generally allowed | Ventilation to the exterior is required. |
| 🏗️ Room Addition | Permit required | city | Valuation-based; includes trade permits. | — | Generally allowed | Any new conditioned footprint requires a building permit, setback/zoning review, and trade permits. Snow loads at altitude affect design. |
| 🪟 Window / Door Replacement | Conditional | city | Usually no fee for in-kind swaps; a permit is needed if the opening is enlarged. | — | Generally allowed | Replacement products must meet the energy code when triggered. Exempt: Same-size, in-kind window/door replacement is generally exempt. |
| 🏘️ Roof Replacement | Conditional | city | Often over-the-counter or exempt for same-footprint re-roof. | — | Generally allowed | Snow-load and ice-dam requirements are reviewed for roof assemblies. Exempt: Same-material, same-slope re-roof is often exempt or over-the-counter; structural deck changes require a permit. |
| 🅿️ Driveway / Parking Pad | Conditional | city | Building permit often not required; curb-cut/right-of-way work is separate. | — | Generally allowed | Mountain/WUI drainage and erosion-control rules may apply; right-of-way permit for curb cuts. Exempt: Replacing a driveway in the same footprint (no new curb cut) is generally exempt. |
| 🏊 Swimming Pool / Spa | Permit required | city | Valuation-based; includes barrier/fencing and electrical bonding review. | — | Generally allowed | Code-compliant barrier required; WUI/mountain communities may add fire-safety rules for pool equipment. |
| 🧱 Retaining Wall | Conditional | city | Valuation-based when over the height threshold. | — | Generally allowed | Sloped mountain lots often trigger engineered retaining-wall requirements. Exempt: PPRBD requires a permit for retaining walls >4 ft; walls ≤4 ft not supporting a surcharge are generally exempt. |
| 💥 Demolition / Teardown | Permit required | city | Valuation-based; set by the issuing city/county. | — | Generally allowed | A demolition permit is required before tearing down a house or attached structure. Local building departments require utility disconnects (electric, gas, water, sewer) and an asbestos/lead-paint clearance for pre-1978 homes before demolition. Mountain/WUI communities may add fire-safety rules for demolition debris. |
| 🚰 Septic System | Permit required | county | Permit fee set by the county/ district health department; engineered systems cost more. | — | Generally allowed | New or replacement onsite wastewater (septic) systems require a permit under Colorado Regulation 43 (CDPHE), administered by county/district health departments. A soil/perc evaluation and engineered design are typically required; conventional and alternative systems are reviewed for site suitability. |
| 🔌 EV Charger | Conditional | city | Electrical permit; fee set by the city/county. | — | Generally allowed | Home EV charging (240V branch circuit + wall-mounted EVSE) requires an electrical permit and must meet the NEC (Article 625). Many Colorado jurisdictions fast-track residential EVSE. A load calculation and possible service upgrade are reviewed. |
| ⚡ Standby Generator | Conditional | city | Mechanical/electrical permit; fee set by the city/county. | — | Generally allowed | A permanently installed standby generator requires mechanical and electrical permits (transfer switch, fuel gas/propane line). Setback, carbon-monoxide ventilation, and noise rules apply; some HOAs restrict generator placement. Mountain/WUI communities may add fire-safety siting rules. |
Frequently asked questions
Who issues building permits in Arapahoe County, Colorado?
Arapahoe County — Public Works and Development (Building Division) is the permitting authority for Arapahoe County. Permitting is split — cities issue for incorporated areas, the county for unincorporated areas. Start at the official portal linked above.
Do I go to the county or my city for a building permit in Arapahoe County?
Permitting is split — cities issue for incorporated areas, the county for unincorporated areas.
What home projects need a permit in Arapahoe County?
The same project types shown in the cheat-sheet above (ADU, deck, fence, shed, solar, and more) — rules follow Colorado state law. Whether the county or your city issues it depends on your property's incorporation status.
How do I apply for a permit in Arapahoe County?
Use the official permit portal linked above. Most offices accept online submissions; have your plans, site information, and contractor details ready before applying.
Sources: Arapahoe County — Public Works and Development (Building Division) · Colorado Office of State Architect — Building Codes · Colorado Energy Office — Building Energy Codes · City and County of Denver — Community Planning & Development (Permits) · Pikes Peak Regional Building Department (Colorado Springs region)