Zoning, building permits and septic rules in Village of Prairie du Sac, Wisconsin

Village of Prairie du Sac’s own rules

• Building permitRequired

  New buildings, additions, alterations, and mechanical/electrical/plumbing work inside Prairie du Sac village

  • No building permit is required for work deemed minor repair (sec. 10-4-6(5))
  • No permit issued unless the property abuts a dedicated street
  • Permit lapses if work not commenced within 6 months or not completed within 1 year

  “no building permit is required for work to be performed which is deemed minor repair under this subsection.”

• Building code adoptedAdopted

  One- and two-family dwellings inside Prairie du Sac village; commercial building code also adopted

  • Commercial building code (SPS 361-366), plumbing (SPS 381-387) and electrical (SPS 316) also adopted by reference
  • Village has certified municipality status under SPS 361.60

  “the administrative code provisions and their appendices describing and defining regulations with respect to one- and two-family dwellings under chapters sps 320-325 of the wisconsin administrative code are hereby adopted and by reference made a part of this chapter as if fully set forth herein.”

• InspectionsRequired

  Buildings under construction inside Prairie du Sac village

  • Inspection stages: footing and foundation; framing, rough electrical, plumbing and heating; insulation; final
  • Inspection within 48 hours of notice by the builder

  inspection response time: <= 48 hours

  “the builder shall notify the building inspector when ready for inspections and the building inspector shall inspect within forty-eight (48) hours of notice all buildings at the following stages of construction:”

• Certificate of occupancyRequired

  New buildings and additions inside Prairie du Sac village

  • Certificate of occupancy not issued until sewer, water, grading and graveling are installed in streets serving the property
  • Zoning ordinance sec. 10-1-1308 separately requires a certificate of occupancy for new or altered buildings and changes in use

  “no new building shall be occupied or otherwise used prior to the issuance of an occupancy permit.”

• Local zoningPresent

  Land inside Prairie du Sac village limits (and its extraterritorial zoning jurisdiction)

  • Zoning ordinance repealed and re-enacted August 9, 2011; amended since; current copy amended through December 18, 2025
  • Chapter also applies in the village's extraterritorial zoning jurisdiction

  “this chapter is applicable to all territory located within the corporate limits and extraterritorial zoning jurisdiction of the village of prairie du sac.”

• Zoning districtsPublished

  Zoning districts inside Prairie du Sac village

  • Districts include R-R, R-1-A, R-1-B, R-2, R-M, B-C, B-H, B-N, B-R, I-1, M-G, M-L, O-R, A-H, A-P, A-T, CON, AIR, PUD, ND plus overlays

  “article 2: establishment of zoning districts 2-1 section 10-1-0200: purpose 2-1 i village of prairie du sac zoning ordinance december 18, 2025 section 10-1-0201: standard zoning districts 2-1 section 10-1-0202: map of standard zoning districts 2-2”

• Minimum dwelling sizeSpecified

  Single-family detached dwellings inside Prairie du Sac village (all zoning districts permitting them)

  • Gross floor area excludes an attached garage

  minimum gross floor area: >= 700 square feet (exclusive of attached garage)

  “the minimum gross floor area shall be 700 square feet, per the definition in section 10-1-0104 but exclusive of an attached garage.”

• Minimum lot sizeSpecified

  R-1-A single-family residential district (R-1-B is 6,600 sf, 60 ft wide)

  • Table text is garbled in extraction; columns read as lot area, lot width, max building coverage, max accessory floor area, landscape surface ratio
  • Note (d) applies

  minimum lot area: >= 9000 square feet · minimum lot width: >= 70 feet

  “r-r single-family residential 21,780 80 30% 1,500 50% r-1-a single-family residential (d) 9,000 70 30% 1,000 50% r-1-b single-family residential (d) 6,600 60 40% 1,000 40%”

  One more reviewed finding on this topic

  • Specified — R-R rural residential single-family district

    “r-r single-family residential 21,780 80 30% 1,500 50% r-1-a single-family residential (d) 9,000 70 30% 1,000 50%”

• SetbacksSpecified

  R-1-A single-family residential district, principal structure or attached garage

  • Table text is garbled in extraction; column order read as front, corner-lot street side, interior side, rear
  • Accessory structure and pavement setbacks differ; see figure 10-1-0403(b)
  • Yard setback adjustments in sec. 10-1-0411 to 10-1-0415 may apply

  front setback: >= 25 feet · corner lot street side setback: >= 15 feet · interior side setback: >= 8 feet · rear setback: >= 30 feet

  “r-r 30 15 12 30 30 8 8 3 10 r-1-a 25 15 8 30 25 4 4 3 r-1-b 25 15 6 20 25 4 4”

  One more reviewed finding on this topic

  • Specified — R-R rural residential district, principal structure or attached garage

    “r-r 30 15 12 30 30 8 8 3 10 r-1-a 25 15 8 30 25 4 4 3 r-1-b 25 15 6 20 25 4 4”

• Lot coverageSpecified

  R-1-A single-family residential district (R-R is also 30%; R-1-B is 40%)

  • Table text garbled in extraction; 30% read as maximum total building coverage
  • Minimum landscape surface ratio 50%

  maximum total building coverage: <= 30 percent · minimum landscape surface ratio: >= 50 percent

  “r-1-a single-family residential (d) 9,000 70 30% 1,000 50% r-1-b single-family residential (d) 6,600 60 40% 1,000 40%”

• Building heightSpecified

  R-R, R-1-A, R-1-B and R-2 residential districts (R-M allows 45 ft / 4 floors)

  • Table text garbled in extraction; read as principal structure 30 ft / 2.5 floors and detached accessory building 15 ft / 1.5 floors
  • Exceptions to maximum height in sec. 10-1-0411 to 10-1-0415
  • Overlay districts such as airport height limitation may be stricter

  maximum principal building height: <= 30 feet (2.5 floors) · maximum accessory building height: <= 15 feet (1.5 floors)

  “residential structure accessory building feet floors feet floors 20 30 2.5 15 1.5 10 20 30 2.5 15 1.5 3 10 20 30 2.5 15 1.5”

• Living in an RVLimited

  Recreational vehicles on residential lots inside Prairie du Sac village

  • Personal-use RV storage allowed with 5 ft setback from all lot lines
  • No RV may be kept on a residential lot lacking a permanent residence or principal building except for temporary dwelling use of 14 days or less
  • RV may not be connected to sanitary sewer or an on-site waste system at any time

  maximum RV dwelling use: <= 14 days per calendar year

  “shall not be used as a dwelling unit for more than 14 days per calendar year, and shall not be used as or considered an accessory structure.”

• Manufactured homesLimited

  Manufactured and mobile homes inside Prairie du Sac village

  • HUD-labeled manufactured homes may be used as single-family detached dwellings if they meet the single-family detached regulations (700 sq ft minimum, permanent foundation, 3:12 roof pitch absent conditional use)
  • Mobile homes only in approved mobile home communities under Title 10 Chapter 7, unless an allowable temporary use

  “mobile homes shall only be allowed in approved mobile home communities meeting the requirement of title 10, chapter 7 of the municipal code, unless used as for an allowable temporary use per subsection (i) of this section.”

• Short-term rentalsLimited

  Tourist rooming houses inside Prairie du Sac village

  • Must be licensed by the state with a designated agent
  • Occupants limited to twice the number of bedrooms
  • No RV, accessory building or tent for living or sleeping
  • Special gatherings prohibited; one parking space per bedroom
  • Districts where permitted not reviewed

  “must be licensed by the state and have a designated agent.”

• Permit processPartial

  Building permit applications inside Prairie du Sac village

  • Plans, plot plan with grade elevations and fees required with application
  • Foundation survey required if within 2 feet of setbacks or on request
  • Zoning permit, conditional use, site plan procedures in zoning ordinance article 13 not reviewed in detail

  “application for a building permit shall be made in writing upon a form furnished by the building inspector and shall state the name and address of the owner of the land”

Still unanswered

We looked and could not find an official answer yet. Silence is not permission; ask Village of Prairie du Sac or Sauk County directly.

• Owner-builder exemption — Owner-builder exemption inside Prairie du Sac village
• Camping on your land — Temporary camping inside Prairie du Sac village
• Tiny homes — Tiny homes inside Prairie du Sac village
• Who permits septic — Septic/POWTS regulation inside Prairie du Sac village
• Septic permit — Septic permits inside Prairie du Sac village

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.