Bolthole Index

Summit County, Colorado

Zoning, building permits and septic rules in the Town of Dillon, Colorado

The Town of Dillon, Colorado sets its own zoning inside town limits1, and most construction there needs a Town of Dillon development permit first2. Building permits are reviewed and inspected by Summit County Building Inspection under contract2. Septic permits in Summit County come from the county Environmental Health Department3; we could not confirm how that applies to individual lots inside town.

At a glance

Zoning
Town of Dillon zoning code (Chapter 16), varies by district1
Development permit
Required from the Town for most construction2
Building permit
Reviewed and inspected by Summit County Building Inspection2
Septic
Summit County Environmental Health issues OWTS permits countywide; town-lot specifics unconfirmed3
Minimum lot, RM zone
6,000 sq ft for a single-family dwelling4
Minimum lot, RE zone
40,000 sq ft, unless approved as a planned unit development5
Camping in Town parks
Only in areas designated for it6

Who to call

Zoning

Town of Dillon Planning & Zoning Department

Town development permits, grading and excavation permits, and zoning questions inside Dillon town limits

(970) 262-3421

275 Lake Dillon Drive, Dillon, CO 80435

Building permits

Summit County Building Inspection Division

Building permit review and inspections for Dillon, under contract with the Town

(970) 668-3170

County Commons, 0037 Peak One Drive, Frisco, CO 80443

Online permits →

Septic permits

Summit County Public Health — Environmental Health Division

Septic (OWTS) permits and inspections in Summit County

(970) 668-9161

360 Peak One Drive, Suite 230, Frisco, CO 80443

Contact details are copied from each office’s official page and were checked against it on October 16, 2026.

Off-grid gear

Going off-grid in Town of Dillon means bringing your own water and power. The kit we’d start with:

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Does Dillon, Colorado have zoning, and what does it allow?

Yes. The Town of Dillon zones land inside town limits under Chapter 16 of its municipal code, and the rules vary by zoning district1. The residential districts we reviewed are RH, RM, RL and RE7.

In the Residential Estate (RE) district, the stated purpose is single-family homes at an average density of about one unit per acre, with a 40,000 sq ft minimum lot unless the site is approved as a planned unit development15. In the Residential Medium Density (RM) district, a single-family dwelling needs at least 6,000 sq ft4, and in RH the minimum is 10,000 sq ft for multi-family dwellings and all other uses8.

Setbacks and height depend on the district. RM and RH front yards are at least 20 ft910, while RE front yards on lots of 40,000 sq ft or more are at least 30 ft11. Maximum building height is 35 ft in RM and RH1213. Accessory dwelling units in RM must meet separate town standards we did not review14.

Do you need a building permit in Dillon, and who issues it?

Most construction inside Dillon town limits needs a Town of Dillon development permit first2. Dillon's planning staff use it to check zoning and signage; the Town page lists new structures, additions, decks, remodels, fences, new driveways and similar projects.

Building permits are a second step. The Town uses the Summit County Building Inspection Department for structural, electrical, plumbing and mechanical code review and inspections2, and a valid Town development permit must be issued before you apply for the building-related permits2. Digging with an excavator or backhoe also needs a grading and excavation permit from the Town2.

Dillon, in conjunction with Summit County, has in general adopted the 2024 series of building codes with amendments2. We could not confirm fees or an owner-builder exemption inside town; ask the Dillon town planner or Summit County Building Inspection15.

How do septic permits work in Dillon?

Septic permits in Summit County are issued by the county Environmental Health Department, which also inspects the installation of new systems and repairs to existing ones3. Colorado requires a permit to construct, alter, install, repair or use an on-site wastewater system when a building is not served by a sewage treatment works16.

We could not confirm whether a given Dillon lot is served by a sewer, so ask the Town before assuming a septic system is needed. If a lot is not sewered, Summit County Public Health's Environmental Health Division handles the permit17.

Summit County's soils are a poor match for conventional drain fields: only about 3% rate as not limited, so expect a site evaluation or an engineered system18.

Can you live in an RV or tiny home in Dillon?

We could not confirm a rule for living in an RV or a tiny home on private land inside Dillon; ask the Dillon town planner before you buy2. What we did confirm is narrower: camping or staying overnight in any Town park, open space or recreation area is unlawful except in an area designated for it6.

The county's RV rule covers unincorporated Summit County, not the town, so it does not answer the question for a Dillon lot. Colorado state law treats Division of Housing-regulated tiny homes as allowed for residential occupancy19, but local zoning still decides where they can sit.

Building a home in Dillon: the steps, in order

  1. Call the Dillon town planner at (970) 262-3421 to confirm your zoning district and which permits your project needs2.
  2. Apply for a Town development permit through the online application2.
  3. If you will dig, get a grading and excavation permit2.
  4. Apply to Summit County Building Inspection for the building permit after the Town permit is issued2; call (970) 668-317015.
  5. Confirm sewer service, or for a lot without it, apply to Summit County Environmental Health for a septic permit17.
  6. Check the state well-permit rule if you plan a private well20.

What stays with Summit County, and what to check before you buy in Dillon

Dillon decides zoning and development permits inside town limits, while Summit County Building Inspection handles building permit review and inspections, and Summit County Environmental Health handles septic permits23. For land outside town limits, use the Summit County page; the county's rules apply to unincorporated land only21.

Before buying, confirm floodplain status, since Colorado floodplain standards apply to development in floodplain areas22, and confirm driveway access onto any state highway, which needs a state access permit23. Summit County's effective property tax rate is 0.3%24. Short-term rental rules inside Dillon are unconfirmed; the Town has a short-term rental hotline on its website.

Watch-outs

  • Septic, sewer service, RV and tiny-home rules, owner-builder exemptions and permit fees inside Dillon are unconfirmed, so call the Town planner at (970) 262-3421 before you rely on any of them2.
  • Summit County's unincorporated rules do not apply inside Dillon town limits, and Dillon's rules do not apply outside them21.
  • A Town development permit must be issued before you apply for the building-related permits2.

Sources

  1. Dillon Municipal Code Sec. 16-3-110 Residential Estate (RE) Zone (Town of Dillon), quoted and re-checked
  2. Town of Dillon Planning & Zoning Department (dillonco.gov)
  3. Onsite Wastewater Treatment Systems (OWTS), quoted and re-checked
  4. Dillon Municipal Code Sec. 16-3-130 Residential Medium Density (RM) Zone (Town of Dillon), quoted and re-checked
  5. Dillon Municipal Code Sec. 16-3-110 Residential Estate (RE) Zone (Town of Dillon), quoted and re-checked
  6. Dillon Municipal Code Sec. 11-4-40 Camping (public parks) (Town of Dillon), quoted and re-checked
  7. Dillon Municipal Code Sec. 16-5-120 PUD development standards (Town of Dillon), quoted and re-checked
  8. Dillon Municipal Code Sec. 16-3-140 Residential High Density (RH) Zone (Town of Dillon), quoted and re-checked
  9. Dillon Municipal Code Sec. 16-3-130 Residential Medium Density (RM) Zone (Town of Dillon), quoted and re-checked
  10. Dillon Municipal Code Sec. 16-3-140 Residential High Density (RH) Zone (Town of Dillon), quoted and re-checked
  11. Dillon Municipal Code Sec. 16-3-110 Residential Estate (RE) Zone (Town of Dillon), quoted and re-checked
  12. Dillon Municipal Code Sec. 16-3-130 Residential Medium Density (RM) Zone (Town of Dillon), quoted and re-checked
  13. Dillon Municipal Code Sec. 16-3-140 Residential High Density (RH) Zone (Town of Dillon), quoted and re-checked
  14. Dillon Municipal Code Sec. 16-3-130 Residential Medium Density (RM) Zone (Town of Dillon), quoted and re-checked
  15. Summit County Building Inspection Division (summitcountyco.gov)
  16. Title 25 - Public Health and Environment - Colorado Revised Statutes 2024 (Colorado statewide rule), quoted and re-checked
  17. Summit County Public Health — Environmental Health Division (summitcountyco.gov)
  18. Share of soils USDA rates "not limited" for a conventional septic drain field (SSURGO). A strict rating: the median county is about 6% and a tenth of counties are 0%, so a low figure means most lots need a site evaluation or an engineered system, not that septic is impossible. Cite it only with that caveat: Bolthole Index county data
  19. Consumers of Manufactured Homes and Tiny Homes - HUD (Colorado statewide rule), quoted and re-checked
  20. Water Administration (Colorado statewide rule), quoted and re-checked
  21. Single-Family Building Permit Checklist, quoted and re-checked
  22. SB24-179 Floodplain Management Program (Colorado statewide rule), quoted and re-checked
  23. Access Permits | Frequently Asked Questions (Colorado statewide rule), quoted and re-checked
  24. Effective property tax rate: Bolthole Index county data

Written October 16, 2026 from the rules quoted below, each taken from an official source and re-checked by an independent reviewer. This is research, not legal advice: rules change, so confirm with the office before you buy or build.

Answers from the rulebook for Town of Dillon

Town of Dillon’s own rules

  • Building code adoptedPartial

    Electrical code inside Dillon town; other building codes (building, residential, fire) not verified

    • Only the electrical code was verified; adopted in full and without amendments

    National Electrical Code edition: 2023

    “is hereby adopted by reference as the Town of Dillon Electrical Code as if fully set out in this ordinance”
  • Local zoningPresent

    Land inside Dillon town limits; Town zoning in Chapter 16 of the Municipal Code

    • Regulations vary by zoning district
    “The purpose of this zone is to provide areas suitable and desirable for single-family homes and accessory uses at an average density of approximately one (1) unit per acre”
  • Zoning districtsPartial

    Zoning districts inside Dillon town; residential districts RH, RM, RL, RE verified, plus MU, C, POS, CA named in other sections

    • Full district list and map not reviewed
    “PUDs that overlay the residential zones (RH, RM, RL and RE)”
  • Minimum lot sizeSpecified

    RE (Residential Estate) zone, inside Dillon town

    • PUD-approved sites may reduce lots to 20,000 sq ft if gross density does not exceed one unit per 0.8 acre
    • Minimum lot width 100 ft (75 ft under PUD)

    minimum lot area: >= 40000 sq ft (PUD 20,000 sq ft)

    “The minimum lot area shall be forty thousand (40,000) square feet, unless the site has been approved under the planned unit development process of the Town”
    2 more reviewed findings on this topic
  • SetbacksSpecified

    RE zone yards inside Dillon town

    • Except as provided in Articles V and XIII
    • Lots under 40,000 sq ft and all detached accessory structures: front 25, side 10, street side 20, rear 20 ft

    front yard (lots >= 40,000 sq ft): >= 30 ft · side yard (lots >= 40,000 sq ft): >= 15 ft · street side yard (lots >= 40,000 sq ft): >= 30 ft · rear yard (lots >= 40,000 sq ft): >= 30 ft

    “Front yards shall be a minimum of thirty (30) feet.”
    2 more reviewed findings on this topic
  • Lot coverageSpecified

    RE zone inside Dillon town

    • Includes all accessory structures

    maximum building coverage: <= 30 percent of lot area

    “All buildings shall not occupy more than thirty percent (30%) of the lot area, including all accessory structures.”
    One more reviewed finding on this topic
  • Building heightSpecified

    RE zone inside Dillon town

    • Except as provided in Articles V and XII
    • 35 ft for lots greater than 40,000 sq ft; 30 ft for lots of 40,000 sq ft or less

    maximum height lots > 40,000 sq ft: <= 35 ft · maximum height lots <= 40,000 sq ft: <= 30 ft

    “no building shall exceed a height of thirty-five (35) feet for lots greater in size than forty thousand (40,000) square feet”
    2 more reviewed findings on this topic
  • Camping on your landLimited

    Camping in Town parks, open space and recreation areas inside Dillon town (not private land)

    • Camping allowed only in areas designated for such use
    • Private-land camping rules not verified
    “It is unlawful for any person to camp or stay overnight in any Town park, open space or recreation area, except in an area designated for such use.”
  • Accessory dwellingsLimited

    Accessory dwelling units in the Residential Medium Density (RM) zone inside Dillon town

    • Must meet requirements of Sections 16-4-35 through 16-4-45 (not reviewed)
    “Accessory dwelling units which meet the requirements as set forth in Sections 16-4-35”

Still unanswered

We looked and could not find an official answer yet. Silence is not permission; ask Town of Dillon or Summit County directly.

  • Building permit — Building permits inside Dillon town
  • Owner-builder exemption — Owner-builder exemption inside Dillon town
  • Inspections — Building inspections inside Dillon town
  • Certificate of occupancy — Certificate of occupancy inside Dillon town
  • Minimum dwelling size — Minimum dwelling size inside Dillon town
16 more unanswered
  • Living in an RV
  • Tiny homes
  • Manufactured homes
  • Who permits septic
  • Septic permit
  • Septic inspection
  • Off-grid sanitation
  • Well permit
  • Mandatory utility hookup
  • Agricultural exemption
  • Subdividing land
  • Driveway access
  • Building in a floodplain
  • Short-term rentals
  • Permit fees
  • Permit process

Each answer was extracted from an official source and independently re-checked against that source by a second reviewer. That is an evidence check, not legal advice. Rules change; confirm with the authority before you buy or build.

Unanswered questions are usually a sign that Town of Dillon publishes no rule on the point, not that none exists. Summit County’s page lists the county offices to call.

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