Building permits, zoning and land rules in Summit County, Colorado

Summit County requires building permits for new structures and listed alterations, remodels, decks, hot tubs and window replacements; re-roofing does not require one unless the work changes the roof structure¹². Every project is different, so there is no standard permit package; the county requires in-person submittal and the plan-review payment at that appointment¹. Plans submitted on or after July 1, 2026 must comply with the adopted 2024 I-Codes, permits applied for on or after May 4, 2026 are subject to the newly adopted fire codes, and new residential structures of at least 4,500 square feet require sprinklers¹². Building Inspection routes applications to internal reviewers, issues building permits, enforces code requirements and conducts building inspections¹³. The county's rules apply to unincorporated Summit County; inside the Town of Silverthorne, new buildings need town site-plan approval before a building permit issues, with single-family and duplex uses excepted in listed districts³. We could not confirm who issues building permits inside Frisco or Dillon, so ask each town.

Start with the Summit County Building Inspection Department at County Commons, 0037 Peak One Drive, Frisco, CO 80443, or call (970) 668-3170¹³. Applications, technical permits, plans and plan changes must be submitted in person by someone who can answer questions; electronic, mailed and courier drop-offs are not accepted, plan-review payment is due at submittal, and applications are not accepted after 4:30 p.m¹.. The county publishes fees by permit type, valuation, area and inspection circumstance; when code-required submittal documents trigger plan review, that charge is 65% of the building-permit fee¹⁴. The Community Development portal supports permit and planning-case searches plus inspection scheduling and cancellation, but it does not establish a complete online application process¹⁵. For parcel zoning, call Planning at (970) 668-4200 or visit Summit County Commons, 37 Peak One Dr., Frisco, CO¹⁶.

Summit County applies its Land Use and Development Code to unincorporated land; incorporated municipalities may administer their own land-use rules². The Town of Silverthorne³, the Town of Frisco⁴ and the Town of Dillon⁵ each zone land inside their limits, so the county's districts do not govern parcels there. In unincorporated areas, district-based controls apply, and site-plan review checks setbacks, building height and site coverage^7,8. Lots created through subdivision review must have a site area and dimensions that conform to the applicable zoning regulations¹⁷, with adequate access for emergency vehicles and other traffic¹⁷. Lots created through the rural land use subdivision process have no stated minimum or maximum size, provided state and county rules such as the Public Health Department's OWTS rules are met¹⁷. A second dwelling is limited: accessory dwelling units on duplex lots and caretaker units go through Class 2 development review, and caretaker units in the M-1 district tied to an active mining operation need a Class 4 Conditional Use Permit⁸. The verified minimum-floor-area schedule applies only to affordable workforce housing units, not necessarily every home⁷. Agricultural operations avoid formal site-plan review unless a building permit is also required, but they remain subject to other applicable requirements⁸. Ask Planning to identify the district and applicable standards before designing¹⁶.

Summit County Environmental Health issues OWTS permits⁶ and inspects installation of every new system and repair^6,18. All OWTS construction, repair and upgrades must be performed by a licensed OWTS contractor, and most systems are or may be required to be designed by a licensed engineer¹⁸. Only about 2.6% of Summit County soils lack severe limits for a conventional drain field, so arrange the site evaluation before fixing the house location¹¹. Properties served by the Snake River Sewer Fund must purchase sewer taps and have service and collection lines inspected before backfilling¹⁹. Environmental Health is at 360 Peak One Drive, Suite 230, Frisco, CO 80443, phone (970) 668-9161²⁰. We could not confirm a complete rule for off-grid sanitation methods other than an approved OWTS, so ask Environmental Health before planning one.

A tiny home on a permanent foundation is allowed in unincorporated Summit County zoning districts where single-family dwellings are permitted, subject to the district and building-code rules⁷. A tiny home on wheels is treated as an RV: long-term occupancy is limited to the RC-5000 and RC-40000 districts, requires a Class 2 conditional-use permit, and is capped at 50 weeks per calendar year with removal for at least 2 weeks⁹. The wheeled unit must also be roadworthy and currently registered, sit on a paved or graveled parking area, and have self-contained sanitation or an approved wastewater connection⁹. We could not confirm a general temporary-camping rule, so ask Planning about the parcel and intended stay¹⁶. The county's floor-area schedule covers affordable workforce housing only and does not establish a general minimum size for every dwelling⁷.

1. Ask Planning at (970) 668-4200 for the parcel's zoning, lot standards and applicable development review^8,16.
2. Evaluate septic early because only about 2.6% of county soils lack severe limits for a conventional drain field¹¹.
3. Obtain the OWTS permit from Environmental Health if sewer is unavailable, and use a licensed OWTS contractor¹⁸.
4. Resolve access before siting the house: county-road access must meet road, subdivision and emergency-access standards, while direct state-highway access requires a CDOT permit and notice to proceed^17,21.
5. Decide who will build. A qualifying owner-occupant may use the Homeowner Builder process for a detached single-family home, associated detached accessory buildings or certain decks, but short-term-rental projects, family trusts and limited liability corporations do not qualify¹⁰.
6. Deliver the building application and plans in person to Building Inspection and pay the required plan-review charge at submittal^1,14.
7. Use the Community Development portal to search the building permit and schedule inspections, and complete the required OWTS installation inspection^6,15.

About 81.1% of Summit County is federal land, so confirm private ownership, boundaries and legal access rather than judging availability from total acreage¹¹. Only about 17.5% of land has a slope of 15% or less, making a survey and realistic driveway and foundation concept especially valuable before purchase¹¹. Only about 2.6% of soils lack severe limits for a conventional septic drain field, so make an acceptable OWTS site part of due diligence¹¹. County-road driveways for single-family and duplex lots need at least 200 feet of sight distance on local access roads or 400 feet on collector roads²¹. Projects subject to floodplain review in unincorporated Summit County carry a separate Floodplain Development permit, listed at $1,280 on the county fee schedule²². Engineering administers county floodplain, road, grading and water-quality rules and can be reached at (970) 668-4202²³. We could not confirm the general well-permit rule or the complete floodplain standards, so ask Engineering before you buy.