Bolthole Index

Rock County, Wisconsin

Zoning, building permits and septic rules in Town of Union, Wisconsin

Town of Union is a town in Rock County, Wisconsin. Town of Union adopts its own zoning, so inside its limits Town of Union’s rules apply, not the county’s. 7 rules below are quoted from official sources and independently re-checked, most recently on October 29, 2026. Rules for unincorporated land are on the Rock County page.

Answers from the rulebook for Town of Union

Town of Union’s own rules

  • Local zoningPresent

    All land and water inside the Town of Union limits (Rock County, WI), administered by the Town of Union board, plan commission and building inspector under the town's Chapter 17 Zoning Ordinance

    • The ordinance states it is adopted under Wis. Stat. 60.61, 60.62 and 60.65.
    • The Chapter 17 PDF is marked 'zoning ordinance - chapter 17 draft 12/17/2014' on several pages; confirm the currently adopted text and amendments with the town clerk before relying on it.
    • Not the Town of Union in Door County, which has its own separate zoning ordinance.
    “the jurisdiction of this ordinance shall include all lands and waters in the town of union, rock county, wisconsin”
  • Zoning districtsPublished

    Zoning districts inside the Town of Union limits

    • Districts: A-1, A-2, A-3, A-4 agricultural; B-1 local business; CHI commercial highway interchange; C-1 lowland conservancy; C-2 highland conservation; R-R rural residential; PUD; MHP mobile home park; SP special purpose; M-1 light industrial.
    • District boundaries are shown on the official zoning map dated October 5, 2006, as amended; the map itself was not opened.
    “the town of union is hereby divided into the following zoning districts”
  • Minimum lot sizeSpecified

    Main single-family residential district: R-R rural residential district inside Town of Union

    • Maximum lot size is less than 3 acres in the R-R district.
    • Two-family dwelling requires minimum lot area of 55,000 sq. ft. per the same table.
    • R-R lots must have soils compatible for on-site sewage disposal per the district purpose.

    minimum lot size: >= 40000 sq. ft.

    “(4) requirements for permitted and conditional uses within the r-r district the following standards shall apply: minimum lot size [...] 40,000 sq. ft.”
  • Camping on your landLimited

    Public camping grounds (camping grounds open to the public with buildings or structures) in the Town of Union agricultural zoning districts

    • The ban applies to conditional uses in agricultural zoning districts; the list begins with camping grounds open to the public with buildings or structures.
    • Temporary uses under section 17.02(3)(d) cover construction shelters and field offices, not camping; no general temporary-camping rule was located.
    • Other districts' camping rules not located.
    “the following conditional uses are not permitted in any agricultural zoning districts”
  • Manufactured homesLimited

    Manufactured and mobile homes (HUD code) on land inside the Town of Union

    • Allowed in the mobile home park district (MHP) or by conditional use under the underlying district.
    • Mobile homes must be placed on a mobile home lot and connected to water, sewerage, electrical and other utilities before occupancy, per the mobile home park provisions.
    “mobile homes and manufactured homes (hud code) are only allowed in the mobile home park district (mhp) or by conditional use as permitted under the corresponding land zoning district”
  • Subdividing landRegulated (with conditions)

    Land divisions in agricultural districts A-1 through A-4 inside Town of Union

    • Plan commission reviews and recommends to the town board on A-1 to A-4 conditional-use land divisions.
    • Town subdivision/land division ordinance and plat rules not opened; this claim covers only the zoning-ordinance review role.
    “to review and recommend to the town board approval, conditional approval or denial of requests for a-1, a-2, a-3, and a-4 conditional use permit land divisions”
  • Permit processPartial

    Zoning and building permit process run by the Town of Union building inspector

    • Only section 17.03 administration text was read; the step-by-step application process is not stated in the text opened.
    • The town ordinance index lists 2006 application flowcharts for zoning changes, land divisions, conditional use permits and variances; not opened.
    “the building inspector may issue building permits which are within strict compliance with the requirements of this ordinance”

Still unanswered

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

  • Owner-builder exemption — Owner-builder construction of a home inside Town of Union
  • Building code adopted — Building code applicable to new homes inside Town of Union
  • Certificate of occupancy — Occupancy certificate for new homes inside Town of Union
  • Minimum dwelling size — Minimum dwelling size in Town of Union R-R and A-1 districts
  • Lot coverage — Lot coverage limits in Town of Union residential and agricultural districts
13 more unanswered
  • Tiny homes
  • Accessory dwellings
  • Who permits septic
  • Septic permit
  • Septic inspection
  • Off-grid sanitation
  • Well permit
  • Mandatory utility hookup
  • Agricultural exemption
  • Driveway access
  • Building in a floodplain
  • Short-term rentals
  • Permit fees

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 Union publishes no rule on the point, not that none exists. Rock County’s page lists the county offices to call.

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