Milliken, CO Zoning, Building Permits & Septic Rules

The Town of Milliken, Colorado (Weld County) adopts its own zoning in Chapter 16 of its municipal code¹. A building permit is required in advance for additions to manufactured homes², and an RV may be used for accommodation for no longer than 72 hours³. Septic permits inside town limits are unconfirmed; Weld County Environmental Health Services is the office to ask⁴.

At a glance

Zoning: Yes, the town zones its own land under Chapter 16 (Land Use Code)¹
Building permit: Required for manufactured-home additions; the town's general permit rules were not confirmed²
RV living: Accommodation in an RV or camper limited to 72 hours³
Accessory dwelling: Allowed in R-1E with a single-family detached home, up to 750 sq ft⁵
Septic: Not confirmed inside town; Weld County Environmental Health Services administers septic permits in the county⁴
Minimum lot (R-1E): Greater of 13,000 sq ft or 4 times the home's floor area⁶

Who to call

Septic permits

Weld County Environmental Health Services (On-Site Wastewater Treatment Systems / Septic)

Septic (on-site wastewater treatment system) permits, site evaluations and inspections in Weld County

(970) 400-6415

1150 O St., Greeley, CO 80631

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 Milliken means bringing your own water and power. The kit we’d start with:

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Does Milliken, Colorado have zoning?

Yes. The Town of Milliken zones the land inside its limits through Chapter 16, its Land Use Code, in Article II, Zoning Districts and Uses¹. Milliken's Residential Estate district (R-1E) is a low-density district intended primarily for single-family homes on large lots¹. Weld County's own zoning applies to unincorporated land, not to property inside Milliken⁷.

In R-1E, the minimum lot area is the greater of 13,000 square feet or 4 times the principal building's floor area⁶. Setbacks are 25 feet in front, 15 feet at the side and on a side street, and 20 feet at the rear⁸. Maximum lot coverage is 40%⁹, and maximum building height is 35 feet¹⁰. We did not review the town's agricultural district limits, so check those with the town before buying a larger parcel.

Can you live in an RV, manufactured home or tiny home in Milliken?

RV living is tightly limited. Milliken's parking code says a trailer or recreational vehicle may not be used as a residential premises, and RVs, camping trailers and campers may be used for accommodation for no longer than 72 hours³. Weld County's allowance for living in an RV on agricultural land while you build applies to unincorporated Weld County, not to property inside the town¹¹.

Manufactured homes are handled through the R-M Manufactured Home Community district, where mobile homes are subject to the town's factory-built and manufactured home standards¹². A manufactured home may not be occupied unless it sits in a manufactured home space and is connected to utilities as appropriate¹³. The minimum lot area in R-M is a 5 acre district and 4,000 square feet per space¹⁴. We found no tiny home provision in the town code sections we read, so ask the town before planning one.

Can you build an accessory dwelling unit in Milliken?

In the R-1E district, Milliken allows an accessory dwelling unit with a single-family detached dwelling, no larger than 750 square feet, under Section 16-4-700 of the town code⁵. The R-M district also allows them⁵. Colorado law separately requires larger Front Range municipalities to allow one ADU per detached home, but whether Milliken is covered depends on its population and planning-organization membership¹⁵.

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

The Town of Milliken, not Weld County, handles building rules inside town limits. The town code states that a building permit is required in advance for any addition to a manufactured home². We could not confirm the town's general permit rules for new homes, garages or sheds, so call the Town of Milliken's building department before you start. Weld County's building permit requirement applies to unincorporated Weld County, not to property in town¹⁶.

For manufactured homes, the building inspector must inspect each unit before occupancy to determine compliance with the town code¹⁷. No occupancy is permitted, and no certificate of occupancy issued, until that inspection is done and connections to public utilities are made¹⁸.

How do septic permits work inside Milliken?

We could not confirm who issues septic permits inside Milliken town limits. Colorado law requires a permit from the local public health agency before anyone builds or alters an on-site wastewater system¹⁹. In Weld County, the Environmental Health Services Division oversees onsite wastewater permitting, including site evaluations, design reviews and inspections⁴.²⁰ is the office to call at (970) 400-6415.

Weld County's policy is to require public sewer where feasible and to limit on-site systems to areas where public sewer is not feasible²⁰. Inside a town, that means connecting to town sewer may be required instead of installing a septic system; confirm with the town.

Building a home in Milliken: the steps, in order

Confirm the zoning district of the parcel with the Town of Milliken and read the district's lot, setback and height limits¹.
Ask the town's building department which building permits your project needs; the town code requires one for manufactured-home additions².
Confirm sewer or septic with the town and with²⁰.
Ask about well rules before drilling; we could not confirm well permits inside town, and Colorado's Division of Water Resources permits wells statewide²¹.
Pass the required inspections and obtain a certificate of occupancy before moving in¹⁸.

What stays with Weld County, and what to check before you buy

For land outside Milliken's limits, Weld County's rules apply: see the Weld County page. Unincorporated Weld County requires building permits under its own building code²² and sets its own zoning²³. Check which side of the town boundary a parcel falls on before relying on either set of rules.

Before buying, confirm the zoning district, sewer availability, and any floodplain permit needs; we could not confirm floodplain permit requirements inside town. Weld County's typical home value is $498,223²⁴ and its effective property tax rate is 0.5%²⁵.

Watch-outs

We could not confirm the town's general building permit requirements, permit fees or owner-builder rules for Milliken; ask the Town of Milliken's building department before you buy or build; the code we read requires a permit for manufactured-home additions².
Septic and well rules inside town limits are unconfirmed; ask Weld County Environmental Health Services at (970) 400-6415²⁰.
Do not rely on Weld County's RV-while-building allowance inside town: the town limits RV accommodation to 72 hours³.

Sources

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.

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

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