Accessory Dwelling Unit (ADU) Permit in Bennett, Colorado

Bennett requires an accessory dwelling unit (adu) permit for: Reviewed per IRC Appendix AQ (ADU-specific provisions) under the 2024 IRC as adopted; Attached ADUs: must be physically separated from the principal unit by a wall or lockable door; minimum 5-foot rear yard setback; maximum height 35 feet (same as principal buildings) subject to IRC R301.3 wood-frame story-height limits; Detached ADUs: maximum height 20 feet, or up to 25 feet with a roof pitch of 8:12 or steeper; minimum 6 feet of separation from any other building on the property (IRC Table R302.1(1)); Complete independent living facilities required: permanent provisions for living, sleeping, cooking, eating, and sanitation; Plot plan and floor plans required as part of the submittal, per the ADU Building Guide; Zoning-level requirements (size limits, lot coverage, parking, owner-occupancy, utility metering) are locally determined; the published guide is a generic Colorado Chapter ICC template, not a Bennett-specific zoning excerpt — confirm current Bennett zoning-code ADU standards directly with the Planning Department before finalizing design, since this guide's zoning-considerations section is explicitly generic ('while specific regulations are local'). If your project isn't listed, confirm with Town of Bennett Community Development Department, Building Department at 303-644-3249 before starting work.

In Bennett, the published Building Permit Fee (valuation-based, per the Town's standard schedule) is: $23.50 minimum, scaling per the valuation tiers in the June 2026 Schedule of Fees. Additional published fees: Plan Review (Administrative) Fee — 65% of Permit Fee. These are the jurisdiction's own published figures — see the fee schedule table and source citations on this page.

Bennett does not publish a plan-review timeline for this permit. Contact Town of Bennett Community Development Department, Building Department at 303-644-3249 for current turnaround.

You'll need: Accessory Dwelling Unit (ADU) Building Guide; Plot Plan and Floor Plans; Building Permit Application. See the required-documents checklist on this page for details on each.

Bennett requires 4 inspection(s) for an accessory dwelling unit (adu) permit, in order: Foundation (detached ADU with new footings), Framing, Rough Electrical / Plumbing / Mechanical, Final Inspection. Schedule each through Town of Bennett Community Development Department, Building Department (303-644-3249).

Apply through Town of Bennett Community Development Department, Building Department at 207 Muegge Way, Bennett, CO 80102. Phone: 303-644-3249, email: bennettbuilding@bennett.co.us. Office hours: Main Town line 303-644-3249 (Building Department extension 1032 per the Building Permits page). Chief Building Official (Steve Jones, Charles Abbott Associates — Bennett's building department is staffed via a CAA contract) holds Drop-In Hours at Town Hall Tuesdays 12:30-1:30 p.m.; email bennettbuilding@bennett.co.us or stevejones@caa.inc to schedule a plan/project review meeting. Additional CAA inspection staff: Brad Jones 720-960-0576 (bradjones@caa.inc), Daniel Willman 720-361-9732 (danielwillman@caa.inc). Inspection requests must be received by 4:00 p.m. the business day before for next-day scheduling; inspections occur Monday-Friday, 7:00 a.m.-5:00 p.m., no specific-window guarantee.. Official information: https://www.bennettco.gov/community-development/page/building-department.

Bennett, Colorado has adopted: 2024 International Building Code (IBC) — effective July 1, 2026 per Town of Bennett 'Building Code Update 2026' notice; 2024 International Residential Code (IRC) — effective July 1, 2026; 2024 International Existing Building Code (IEBC) — effective July 1, 2026; 2024 International Mechanical Code (IMC) — effective July 1, 2026; 2024 International Energy Conservation Code (IECC) — effective July 1, 2026; 2024 International Plumbing Code (IPC) — effective July 1, 2026; 2024 International Fire Code (IFC) — effective July 1, 2026 for the Town's own adoption (Bennett-Watkins Fire Rescue, the separate special district that performs fire plan review/inspection for Bennett, Watkins, and unincorporated Adams/Arapahoe County, is separately shown by its own website as still operating under the 2018 IFC as of this review — confirm current fire-district code edition directly with Bennett-Watkins Fire Rescue at 303-644-3572, since fire code adoption is that district's own action, not the Town Building Department's); 2024 International Fuel Gas Code (IFGC) — effective July 1, 2026; 2024 International Swimming Pool and Spa Code (ISPSC) — effective July 1, 2026 (new code title added in this cycle; no 2018-cycle equivalent was listed); Colorado Model Electric and Solar Ready Code — effective July 1, 2026 (statewide model code addressing EV/solar readiness, adopted by the Town as part of the 2026 cycle); 2025 Colorado Wildfire Resiliency Code — effective July 1, 2026; 2023 National Electrical Code (NEC) — currently in effect per the Town's Adopted Building Department Codes list (the NEC was not part of the July 1, 2026 update batch and continues under its existing adoption); PRIOR CYCLE (2018 codes), still governing permits issued before July 1, 2026 that have not expired: 2018 IBC, 2018 IRC, 2018 IPC, 2018 IMC, 2018 IEBC, 2018 IFC, 2018 IFGC, 2018 IECC.; Transition rule (per the Town's 'Building Code Update 2026' notice, verified directly): the Town issued NO permits under the 2024 cycle before July 1, 2026. Permits issued under the 2018 cycle before July 1, 2026 may finish construction on that code cycle, UNLESS the permit expires after July 1, 2026, in which case renewal or a new permit after that date requires meeting 2024 code. All permits issued on or after July 1, 2026 must meet the 2024 I-codes. EXCEPTION: 8 named residential master-plan developments currently under construction on 2018-cycle approved master plans (Bennett Avenue Townhomes; Bennett Crossing Filing 5 Phases 1A/1B; Bennett Ranch Filing 1; Bennett Ranch Filing 2; Horizon Village; Muegge Farms Filing 4 Phases 4A/4B; Muegge Farms Filing 5; Muegge Farms Filing 7 Phase 1) are given until July 1, 2028 to finish their current phase under the 2018 cycle. As of this file's lastVerified date (2026-07-06), the 2024 cycle is the live, current adopted code for new permit applications outside these named exceptions.. Local amendments apply — see the Bennett overview page for the full list.

Per the Town's published ADU Building Guide, detached ADUs are capped at 20 feet, except that a steeper roof pitch of 8:12 or greater allows up to 25 feet. Detached ADUs converted from an existing structure may exceed 20 feet if no changes are made to the building's height, floor area, or roof form.