Building a Shed in Iowa? Here's When You Need a Permit
Quick answer
Shed permit rules in Iowa vary widely by city. Des Moines requires a permit for any shed over 120 square feet. West Des Moines exempts portable sheds under 200 square feet that aren't on a permanent foundation. Smaller cities and rural counties generally follow the IRC's 200-square-foot exemption. All sheds must meet local zoning setbacks and lot coverage limits. Check with your specific city's building department before building.
Iowa at a glance
Building code adopted
Iowa State Building Code (Chapter 103A, Code of Iowa), based on the International Building Code and International Residential Code. The state establishes minimum standards, but enforcement and amendments are handled locally by cities and counties.
Common permit threshold
120 sq ft in many cities, 200 sq ft in counties — the threshold varies significantly across Iowa, with larger cities often using a stricter 120 sq ft limit.
Did you know?
Iowa is one of the few states where the largest city has a meaningfully stricter shed threshold than the surrounding suburbs. Des Moines caps permit-free sheds at 120 square feet and limits the total shed height to 17 feet, while nearby West Des Moines allows portable sheds up to 200 square feet without a permit. This means the same shed could be legal without a permit in one city and require full drawings and inspections just across the city line.
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A State Where the Threshold Depends on Your Address
Iowa's shed permit rules are defined more by local variation than statewide consistency. The state's building code framework, established under Chapter 103A of the Code of Iowa, sets minimum standards but leaves enforcement, fee schedules, and specific exemption thresholds to individual cities and counties. The result is a patchwork where your permit obligations depend heavily on which side of a city boundary line your property falls on.
The IRC's standard 200-square-foot exemption is used by many Iowa counties and smaller cities. But several of the state's largest cities have adopted stricter thresholds. Des Moines uses 120 square feet as its maximum shed size before a building permit is required. Scott County (covering Davenport) also uses 120 square feet. West Des Moines takes a different approach, exempting portable sheds under 200 square feet that aren't on a permanent foundation while requiring permits for permanent structures of the same size.
This variation means there's no shortcut to checking with your specific city's building department. Even within the Des Moines metro area, three neighboring cities can have three different rules.
For a broader look at how Iowa compares nationally, see our national guide to shed permits.
How Five Iowa Cities Handle Shed Permits
Des Moines: 120 Square Feet and Strict Standards
Des Moines has one of Iowa's more detailed shed ordinances. The maximum size for a permit-exempt storage shed is 120 square feet. If your shed exceeds 120 square feet, it's treated as a new detached garage and requires a full building permit with construction drawings.
Des Moines adds several specific requirements. Sheds must be in the rear yard, at least 5 feet from side and rear property lines and at least 3 feet from the house. The maximum height is 17 feet to the peak. The maximum ground floor area of all accessory buildings combined (including any detached garage) is limited to 20% of the rear yard area. Exterior wall height cannot exceed 12 feet, and exterior surfaces must be residential in character with pre-finished colored steel or compatible materials — galvanized metal is not permitted.
The city also limits each residential property to a combined total of accessory building area that covers no more than 10% of the total lot, not to exceed 1,000 square feet. Contact the Des Moines Permit and Development Center at (515) 283-4200 for specific questions.
Cedar Rapids: Standard 200-Square-Foot Exemption
Cedar Rapids follows the IRC's 200-square-foot exemption. One-story detached sheds used for storage, tools, or similar purposes don't need a building permit when the floor area stays at or below 200 square feet. The city's building division processes permits for larger sheds with typical fees of $50–$150 and review times of 5–10 business days.
Cedar Rapids enforces standard setback requirements for accessory structures. Sheds must be in the rear yard, behind the principal structure, and meet the setback distances for the specific zoning district.
Davenport: 120 Square Feet Under Scott County Rules
Davenport and Scott County use a 120-square-foot threshold, lower than the IRC standard. Scott County's construction code specifically deletes the IRC's standard exemption and replaces it with the stricter threshold. Sheds over 120 square feet require a permit. One-story wood-frame garages and accessory buildings up to 720 square feet can use a floating slab-on-grade foundation with a concrete perimeter grade beam, rather than full frost-depth footings.
Scott County's frost depth requirement is 42 inches for structures connected to underground utilities. The county also requires all buildings or portions containing mechanical installations to have a continuous perimeter frost-free foundation.
Iowa City: 200 Square Feet Through Johnson County
Iowa City and Johnson County use the 200-square-foot exemption. The county's building FAQ is clear: "A permit is not required to construct a detached building that is 200 square feet or less," limited to one-story accessory structures used as tool and storage sheds. The county notes that permit applications may take 5–10 business days to process, with complete submissions reviewed faster.
Iowa City adds local zoning requirements including setback distances, lot coverage limits, and placement rules. Even sheds under 200 square feet must meet these standards.
West Des Moines: The Portable Shed Distinction
West Des Moines takes a notably different approach by distinguishing between portable and permanent sheds. Portable sheds under 200 square feet that are not placed on a permanent foundation are exempt from building permits. This exemption recognizes that many pre-built sheds delivered on skids are functionally movable.
For permanent accessory buildings, West Des Moines enforces detailed standards. The combined square footage of all detached structures cannot exceed 10% of the total lot, with a maximum of 1,000 square feet. Structures up to 1,024 square feet may use slab-on-grade construction with a perimeter thickened to at least 12 inches deep and 12 inches wide. The maximum roof height is 20 feet, and exterior wall height can't exceed 12 feet. All detached accessory structures must be residential in character with architectural features matching the principal structure.
Find your Iowa city
Get the exact shed permit requirements for your area.
Foundation Requirements: Iowa's 42-Inch Frost Depth
Iowa's frost depth is 42 inches across most of the state, making full frost-depth foundations expensive for sheds. Fortunately, Iowa jurisdictions provide alternatives for smaller structures.
Sheds under the permit-exempt threshold (120 or 200 square feet depending on city) can sit on gravel pads, concrete blocks, pressure-treated skids, or pier blocks. No frost-depth footings are required. Anchoring is recommended but enforcement varies.
Sheds from the permit threshold to 720–1,024 square feet can often use slab-on-grade construction with a thickened perimeter edge. Scott County allows floating slabs for wood-frame accessory buildings up to 720 square feet. West Des Moines extends this to 1,024 square feet. The thickened edge (typically 12 inches deep and 12 inches wide) acts as a grade beam, providing stability without going to full frost depth.
Sheds over the slab-on-grade limit, or those connected to underground utilities, must have foundations extending to 42 inches below grade. This is a significant cost increase and is one reason many Iowa homeowners keep their sheds at or below the slab-on-grade threshold.
Wind, Snow, and Iowa's Prairie Climate
Iowa's location in the central plains exposes sheds to two significant weather demands: wind and snow.
Wind loads are a serious consideration, particularly in western Iowa and along the open corridors between cities. Most Iowa jurisdictions require structures to be designed for 90 mph or higher wind speeds. Anchoring sheds against wind uplift and lateral forces is important even for small structures. The standard approach is ground anchors at each corner, with anchor straps or bolts rated for the local wind speed.
Snow loads across Iowa range from about 30 psf in the southern part of the state to 40 psf in the northern counties. These are moderate by national standards but still require proper roof framing. Pre-built sheds from regional manufacturers are typically designed for Iowa's snow loads. Sheds purchased from national retailers may need to be verified against local requirements.
Iowa is also in a high-tornado-risk area. While standard building codes don't design sheds for direct tornado hits, proper anchoring significantly reduces the chance of a shed becoming airborne debris in high winds. This is both a code requirement and a common-sense safety measure.
Agricultural Exemptions: Iowa's Farm Heritage
Iowa's agricultural roots mean that farm buildings often receive different treatment than residential accessory structures. Genuine agricultural operations on qualifying farmland may be exempt from standard building permit requirements in many Iowa counties. Scott County specifically lists "an agriculturally-exempt farmer" among those not required to obtain permits.
However, this exemption is narrowly defined. It applies to commercial agricultural operations on land zoned for agriculture, not to residential homeowners who happen to grow a garden. A storage shed for lawn equipment on a suburban lot doesn't qualify, even if the property was historically farmland. The definition of a qualifying operation varies by county and is typically linked to the property's agricultural tax classification.
If you believe your property qualifies for an agricultural exemption, contact your county assessor's office and building department. They can confirm whether your operation meets the local definition.
Lot Coverage, Height, and Aesthetic Rules
Iowa cities generally enforce strict controls on the total area and appearance of accessory buildings.
Lot coverage limits are universal. Des Moines caps all accessory buildings at 10% of total lot area, not to exceed 1,000 square feet. West Des Moines uses the same formula. Smaller cities typically use similar percentages. This means on a 7,000-square-foot lot, your total shed and detached garage area can't exceed 700 square feet.
Height limits range from 17 to 20 feet to the roof peak in most cities, with exterior wall heights capped at 12 feet in Des Moines and West Des Moines. Many cities require accessory buildings to be shorter than the principal structure.
Aesthetic requirements are increasingly common in Iowa's cities. Des Moines and West Des Moines require accessory buildings to be "residential in character" with roof slopes, overhangs, and accent colors similar to the principal structure. Metal cladding must be pre-finished and colored. Galvanized metal, tent material, tarps, and membrane structures are generally prohibited as shed exteriors in residential zones.
Electrical, Plumbing, and Mechanical
Utility connections trigger additional permits in Iowa regardless of the shed's size. Electrical, mechanical, and plumbing permits must be applied for separately by state-licensed contractors. Iowa handles trade licensing at the state level — electrical and plumbing contractors must hold state licenses issued through the Iowa Division of Labor.
Homeowners in Iowa can perform their own electrical work on owner-occupied single-family residences and their accessory structures in many jurisdictions, but the work must be inspected by the local authority or the state electrical inspector. If you hire someone, they must be licensed.
HOA Restrictions
Iowa has a growing number of Homeowners Association (HOA)-governed communities, especially in the newer developments around Des Moines, West Des Moines, Ankeny, and the Cedar Rapids suburbs. HOA restrictions on sheds commonly include architectural committee approval, matching materials and colors, size limits often well below zoning maximums, and in some cases prohibitions on site-built sheds in favor of approved manufacturer models.
Iowa's Homeowners Association Act (Chapter 499B) gives associations enforcement powers. Always check your HOA's covenants and get written approval before building.
Consequences of Skipping the Permit
Building without required permits in Iowa can lead to stop-work orders, fines, retroactive permits with penalties, removal orders, and sale complications. Permit fees across Iowa are generally modest — $50–$200 for most shed projects — and the cost of compliance is minimal compared to the potential consequences.
If you're also planning a garage or carport alongside your shed, remember that Iowa cities cap total accessory building area. Des Moines' 20% of rear yard limit and West Des Moines' 10% of lot area cap both include all detached structures combined.
For an overview of all building permit requirements in Iowa — including decks, fences, pools, and more — see our complete Iowa building permit guide.
| City | Permit threshold | Typical fee | Review time |
|---|---|---|---|
| Des Moines | 120 sq ft (larger = treated as new garage; permit required) | $50–$200 (valuation-based) | 1–3 weeks |
| Cedar Rapids | 200 sq ft, one story, no utilities | $50–$150 | 5–10 business days |
| Davenport | 120 sq ft (Scott County); zoning for all sizes | $50–$150 | 5–10 business days |
| Iowa City | 200 sq ft (Johnson County); zoning still applies | $50–$100 | 5–10 business days |
| West Des Moines | 200 sq ft portable (no permanent foundation) | $75–$200 (valuation-based) | 1–3 weeks |
City names link to full city-specific guides.
Ready to build your shed?
Professional shed plans that meet Iowa building code requirements. Permit-ready drawings you can submit with your application.
Frequently asked questions
Why do permit thresholds vary so much across Iowa?
Iowa's State Building Code establishes minimum construction standards, but enforcement and permit thresholds are set at the city and county level. The state code allows local jurisdictions to adopt the International Residential Code with their own amendments, and different communities have chosen different exemption thresholds. Des Moines uses 120 square feet, West Des Moines exempts portable sheds under 200 square feet, Johnson County uses 200 square feet, and Scott County uses 120 square feet. There's no single statewide answer, which is why checking with your specific city is the first step.
What counts as a portable shed in West Des Moines?
West Des Moines distinguishes between portable and permanent sheds. Portable sheds under 200 square feet that are not placed on a permanent foundation are exempt from building permits. Once you add a concrete slab, frost footings, or utility connections, the shed becomes a permanent structure and needs a building permit. The city's ordinance specifically lists portable sheds under 200 square feet as exempt. However, all sheds, portable or permanent, must comply with zoning setback, height, and lot coverage requirements.
Are agricultural buildings exempt from permits in Iowa?
Iowa has a strong agricultural heritage, and genuine agricultural buildings on qualifying farm operations may be exempt from standard building permit requirements. Scott County specifically mentions that an agriculturally-exempt farmer is not required to obtain standard building permits. However, this exemption applies to commercial agricultural operations, not to residential sheds on properties that happen to be in agricultural zones. The definition of a qualifying agricultural operation varies by jurisdiction. Contact your county assessor's office and building department to determine if your property qualifies.
Does my Iowa shed need a foundation below the frost line?
It depends on the size. Iowa's frost depth is 42 inches in most of the state. Sheds under the permit-exempt threshold can sit on gravel pads, concrete blocks, or treated timber skids without going below the frost line. For larger sheds that require permits, some cities allow slab-on-grade construction for structures up to 720 square feet or 1,024 square feet, with a thickened perimeter edge. Structures over these thresholds, or those connected to underground utilities, typically need frost-depth foundations at 42 inches below grade.
Can I use a metal-sided shed in a residential neighborhood in Iowa?
Many Iowa cities require that residential accessory buildings be compatible with the principal structure in architectural style, materials, and color. Des Moines specifically requires exterior surfaces to be pre-finished colored steel or similar material — galvanized metal is generally not acceptable as a visible exterior finish in residential zones. West Des Moines has similar requirements. Some cities require a conditional use permit for metal buildings in residential areas. Check your city's ordinance before purchasing a metal shed.
Shed permits in Iowa cities
Select your city for specific shed permit rules, fees, and application details.
Permit requirements vary by city and county. The information in this guide provides general guidance for Iowa based on common local building codes. Always verify requirements with your local building department before starting your project.