Bolthole Index

Marshall County, Iowa

Zoning, building permits and septic rules in Marshalltown, Iowa

Inside Marshalltown, Iowa, the city requires a building permit for new construction, additions and alterations, issued by the city Building Division1. The city also administers its own zoning under Chapter 156 of its city code2. Septic permits and private wells are county and state matters in Marshall County, not city counter items3; we could not confirm which office covers septic inside city limits.

At a glance

Building permit
Required for new construction, additions and alterations inside city limits1
Zoning
City-run zoning under Chapter 156 of the city code2
Building codes
2021 International Residential and Building Codes, plus 2020 National Electrical Code4
Manufactured homes
Allowed on their own lot in all districts, subject to lot standards5
Septic
Not confirmed inside city limits; county and state share private sewage rules3
Owner-builder
Not confirmed for city permits; state contractor-registration exemption exists6

Who to call

Building permits

City of Marshalltown Building Division

Building, demolition and trade (electrical, mechanical, plumbing) permits inside Marshalltown city limits

641-754-5756

[email protected]

36 N. Center Street Marshalltown, IA 50158

Zoning

City of Marshalltown zoning ordinance (Title XV, Chapter 156)

City zoning districts and standards inside Marshalltown

Septic permits

Marshall County Environmental Health

County sanitarian for septic systems and private wells in Marshall County

641-844-2707

[email protected]

Courthouse 1 E. Main St., Suite 140 Marshalltown, IA 50158

Contact details are copied from each office’s official page and were checked against it on October 24, 2026.

Off-grid gear

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

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Do you need a building permit in Marshalltown, Iowa?

Yes. The City of Marshalltown requires building permits, demolition permits and trade permits for electrical, mechanical and plumbing work on alterations, additions and new construction17. Construction may proceed once the permit is issued, and the city asks applicants not to send payment until it confirms the total fee8.

Building permit fees in Marshalltown come from the ICC Building Valuation Data table9. Residential trade permits are flat: $125 for new residential construction, which is included in the building permit, and $85 for residential alterations; plan review adds 65% of the permit fee9.

The city operates under the 2021 International Building Code and 2021 International Residential Code, among others4.

Who issues building permits in Marshalltown, and how do you reach them?

The Marshalltown Building Division issues building permits inside city limits. Applications go to the city in person, by mail or by email to [email protected]87. The division's phone is 641-754-5756 and its office is at 36 N. Center Street7.

The city's page links a permit process information sheet, a building permit application and a separate trade permit application8.

The Marshall County Planning & Zoning office handles unincorporated land, so it is the wrong counter for a lot inside city limits. For land outside Marshalltown, see the Marshall County page.

Does Marshalltown have zoning, and what does it mean for homes and lots?

Yes. Marshalltown administers its own zoning ordinance, found in Title XV Land Usage, Chapter 156 of the city code210. Published districts include AG agricultural, RR rural residential, RL low-density residential and RM medium-density residential, among others11.

Standards depend on the district. In the RL district, a conventional single-family detached lot needs at least 9,000 square feet and 75 feet of width, with a 35-foot height limit1213. A manufactured or modular home on its own lot is allowed in every district, subject to those lot standards5.

Replatting an existing lot falls under Chapter 157, Land Subdivision Regulations14. We could not confirm minimum home size, lot coverage or accessory dwelling rules in the city code; ask the Building Division before you design.

How do septic permits work in Marshalltown?

Septic and private wells are not part of the city's building permit. Iowa shares private sewage disposal regulation between the Iowa Department of Natural Resources and county boards of health3, and Marshall County regulates systems serving four homes or fewer15. Installing or altering a private system requires a permit16, and new dwellings need a county well permit17.

We could not confirm whether the city requires sewer connection or which office permits septic on a lot inside city limits. Most city lots are likely served by city sewer, but call Marshall County Environmental Health18 and the Building Division before relying on a septic system.

Iowa also requires an inspection of private sewage systems serving one to four dwelling units before qualifying ownership transfers19.

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

We could not confirm Marshalltown's rules on long-term RV living, temporary camping or accessory dwellings, so do not assume any of them is allowed on a city lot. Ask the Building Division at 641-754-5756 before you move an RV onto a lot7.

Iowa law lets cities regulate accessory dwelling units in any zoning district where a single-family residence is allowed, with a size cap of 1,000 square feet or 50% of the single-family residence, whichever is larger20. Whether Marshalltown's districts apply that cap in a particular zone is not something we could confirm.

Outside city limits, Marshall County has its own RV habitation rule; see the Marshall County page.

Building a home in Marshalltown: the steps, in order

  1. Confirm your lot's zoning district under Chapter 156 and check lot width, area and height for that district211.
  2. If you are dividing or replatting the lot, review Chapter 157 first14.
  3. Fill out the city's building permit application and, for electrical, plumbing and mechanical work, the trade permit application8.
  4. Submit to the Building Division by email, mail or in person, and wait for the total fee before paying87.
  5. Build to the adopted codes, including the 2021 International Residential Code4.
  6. For any private septic system or well, contact Marshall County Environmental Health18.

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

Septic and private wells run through the county sanitarian and state rules, not city zoning318. Driveways that connect to a county road need a county engineer permit, though a lot on a city street is a city question21. Floodplain rules inside city limits are unconfirmed; ask the city before you buy near a creek or river.

For context, Marshall County's farmland value is about $9,375 per acre22, typical home value is about $196,65823, and the county's effective property tax rate is 1.5%24. These are county-level figures, not Marshalltown-only. The nearest city of 100,000 or more is about 45 miles from the county center25.

Watch-outs

  • Do not use Marshall County's unincorporated rules for a lot inside Marshalltown; the county rules apply only outside city limits26.
  • We could not confirm Marshalltown's rules on RVs, accessory dwellings, minimum home size, lot coverage, owner-builder exemptions or floodplain development; ask the Building Division at 641-754-57567.
  • Iowa's contractor-registration exemption for work on your own property does not by itself waive city building permits or inspections6.

Sources

  1. City of Marshalltown - Building Division (Marshalltown), quoted and re-checked
  2. City of Marshalltown - Zoning Ordinance page (Marshalltown), quoted and re-checked
  3. Iowa Code §455B.172, Jurisdiction of department and local boards (Iowa statewide rule), quoted and re-checked
  4. City of Marshalltown - Building Division (Marshalltown), quoted and re-checked
  5. Chapter 156 Zoning Article B - District Development Standards (printed 4/7/2022) (Marshalltown), quoted and re-checked
  6. Iowa Code 2026, Chapter 91C — Construction Contractors (2026 county census)
  7. City of Marshalltown Building Division (marshalltown-ia.gov)
  8. City of Marshalltown - Building Division (Marshalltown), quoted and re-checked
  9. City of Marshalltown - Building Division (Marshalltown), quoted and re-checked
  10. City of Marshalltown zoning ordinance (Title XV, Chapter 156) (marshalltown-ia.gov)
  11. City of Marshalltown - Zoning Ordinance page (Marshalltown), quoted and re-checked
  12. Chapter 156 Zoning Article B - District Development Standards (printed 4/7/2022) (Marshalltown), quoted and re-checked
  13. Chapter 156 Zoning Article B - District Development Standards (printed 4/7/2022) (Marshalltown), quoted and re-checked
  14. Chapter 156 Zoning Article B - District Development Standards (printed 4/7/2022) (Marshalltown), quoted and re-checked
  15. Private Sewage Disposal and Septage, quoted and re-checked
  16. IAC 567—Chapter 69 Private Sewage Disposal Systems, quoted and re-checked
  17. Wells, quoted and re-checked
  18. Marshall County Environmental Health (marshallcountyia.gov)
  19. Iowa Code §455B.172, Jurisdiction of department and local boards (Iowa statewide rule), quoted and re-checked
  20. legis.iowa.gov (Iowa statewide rule), quoted and re-checked
  21. Engineer Permits, quoted and re-checked
  22. Farmland value per acre (USDA census): Bolthole Index county data
  23. Typical home value (Zillow): Bolthole Index county data
  24. Effective property tax rate: Bolthole Index county data
  25. Straight-line distance from the county center to the nearest city of 100,000+ people: Bolthole Index county data
  26. Zoning Applications & Permits, quoted and re-checked

Written October 24, 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 Marshalltown

Marshalltown’s own rules

  • Building permitRequired

    Alterations, additions and new construction inside Marshalltown city limits

    • Building permits, demolition permits and trade permits (electrical, mechanical, plumbing) are required per the city page; construction may proceed after the permit is issued.
    • Trade permits for residential projects carry flat fees per the city page.
    “the city of marshalltown requires building permits, demolition permits and trade permits (electrical, mechanical and plumbing) for items including, but not limited to; alterations, additions to residential and commercial buildings and new construction for all uses”
  • Building code adoptedAdopted

    New construction and alterations inside Marshalltown city limits

    • The city lists 2021 International Building Code, 2021 International Residential Code, 2021 International Fire Code, 2021 International Existing Building Code, 2021 Uniform Plumbing Code, 2021 International Mechanical Code (state of Iowa adopted) and 2020 National Electrical Code as the codes it currently operates under.
    “the city is currently operating under the following codes.”
  • Local zoningPresent (with conditions)

    Land inside Marshalltown city limits: the city administers its own zoning ordinance (Title XV Land Usage, Chapter 156).

    • Zoning districts, uses and dimensional standards are set by Chapter 156 of the city code; the Article B text printed 4/7/2022 is the copy reviewed here and the current American Legal Publishing text was not opened for each section.
    • Lands outside city limits are not covered by this claim.
    “zoning can be found in title xv land usage. chapter 156.”
  • Zoning districtsPublished

    Land inside Marshalltown city limits

    • Districts listed on the city page include AG, RR, RL, RM, RH, MU, UC, GC, GI, PUD, PI, REC and historic overlays; the Article B table of districts (Table 156.B.002-1) was partially legible in the PDF text.
    “district description ag agricultural district rr rural residential district rl low-density residential district rm medium-density residential district”
  • Minimum lot sizeDistrict specific (with conditions)

    Single-family detached dwelling in the RL low-density residential district inside Marshalltown city limits (conventional development)

    • Minimum lot area is calculated per dwelling unit; minimum lot width is calculated for the entire lot (Table 156.B.004-1 footnote 3).
    • Cluster development in RL has a smaller 6,500 sq ft minimum lot per the same table; lot averaging under 156.B.008.B may apply.

    minimum lot area, single-family detached: >= 9000 sq ft (RL conventional development) · minimum lot width, single-family detached: >= 75 ft (RL conventional development)

    “single-family detached 4.40 n/a 9,000 s.f. 75 ft. 35 ft. 30 ft. 8 ft. 7 ft.”
  • Building heightDistrict specific (with conditions)

    Single-family detached dwelling in the RL low-density residential district inside Marshalltown city limits (conventional development)

    • Height is measured per Table 156.B.008.A-1 (measurement methodology) and the height limit applies to the principal building.

    maximum building height: <= 35 ft (RL conventional single-family detached)

    “single-family detached 4.40 n/a 9,000 s.f. 75 ft. 35 ft. 30 ft. 8 ft. 7 ft.”
  • Manufactured homesAllowed

    A manufactured or modular home placed as a single-family detached dwelling on its own lot inside Marshalltown city limits

    • Footnote to the residential district table says the allowance applies to all districts; the lot and setback standards of Table 156.B.004-1 still apply.
    “5. including a manufactured or modular home on its own lot (applies to all districts).”
  • Subdividing landRegulated (with conditions)

    Land divisions and replats inside Marshalltown city limits

    • Chapter 157 (Land Subdivision Regulations) governs replatting; the Chapter 157 text was not opened.
    “refer to chapter 157, land subdivision regulations, for requirements related to replatting existing lots.”
  • Permit feesPublished

    Building and trade permits inside Marshalltown city limits

    • Building permit fees are calculated from the ICC Building Valuation Data table, updated twice a year, per the city page; the city page lists trade permit flat fees for new residential construction ($125, included in the building permit), residential alterations ($85), appliance replacement ($62) and commercial trade permits based on valuation ($50 for the first $1,000 and $5 per additional $1,000).
    • Plan review fees are 65% of permit fees per the city page.

    trade permit fee, new residential construction: 125 USD (fees are included in building permit) · trade permit fee, residential alterations: 85 USD · plan review fee: 65 percent of permit fee

    “the city uses the the icc building valuation data (bvd) table to establish fees.”
  • Permit processPublished

    Building and trade permit applications inside Marshalltown city limits

    • The city page links a building permit process information sheet (English and Spanish), a building permit application form, and a trade permit application form.
    • Do not submit payment until the city notifies the applicant of the total fee.
    “all permits should be submitted directly to the city in person, by mail or via email to [email protected]”

Still unanswered

We looked and could not find an official answer yet. Silence is not permission; ask Marshalltown or Marshall County directly.

  • Owner-builder exemption — Owner-builder permit exemption inside Marshalltown city limits
  • Certificate of occupancy — Certificate of occupancy for new dwellings inside Marshalltown city limits
  • Minimum dwelling size — Minimum dwelling floor area inside Marshalltown city limits
  • Lot coverage — Lot coverage inside Marshalltown city limits
  • Living in an RV — Long-term RV occupancy inside Marshalltown city limits
11 more unanswered
  • Camping on your land
  • Accessory dwellings
  • Who permits septic
  • Septic permit
  • Septic inspection
  • Off-grid sanitation
  • Well permit
  • Mandatory utility hookup
  • Agricultural exemption
  • Building in a floodplain
  • Short-term rentals

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

← All of Marshall County: county rules, score and offices