Marathon County, WI Building Safety: Building Permits (2026)
Key Facts
- Permit trigger
- Erection of any deck (a structure)
- Exemption
- Ordinary maintenance/repair; minor structures
- Setback rule
- Deck perimeter can't cross setback line
- Coverage
- Unincorporated towns adopting county zoning only
Summary
A deck is a structure under Marathon County's zoning code, so building one in a town under county zoning requires a zoning permit before construction starts, unless it counts as a minor structure.
A zoning permit shall be issued before any of the following may occur:1.Prior to the erection, structural alteration, or moving of any building or structure except as exempted in this section.2.Prior to the establishment of a new use, whether the land is currently vacant or if a substantial change in land use is proposed.3.Prior to any change in use of an existing building or structure.B.Exemptions. A zoning permit shall not be required for the following:1.Alterations involving ordinary maintenance and repair.2.For new minor structures as defined in Section 17.902.
Official source re-checked September 7, 2026: no newer edition of the code had been published (publisher’s edition: Code of Ordinances: Supplement 59).
Full Breakdown
The code defines a deck as a structure, and Sec. 17.802.01.A requires a zoning permit before any building or structure is erected, altered, or moved, with exemptions only for ordinary maintenance/repair and 'new minor structures' under Sec. 17.902. Sec. 17.401.03 additionally bars a deck's outer perimeter from extending into a required setback area, and decks in shoreland areas fall under the separate Chapter 22 shoreland ordinance. This permit rule applies only in unincorporated towns that have adopted the county's zoning ordinance.
Violations & Fines
Building a deck without the required permit is a zoning violation under Sec. 17.807: the Zoning Administrator can issue a notice, and unresolved violations draw a forfeiture under Ch. 25.04 plus removal.
Frequently Asked Questions
Do I need a permit to build a deck in Marathon County?
Can my deck extend into my setback?
Sources & Official References
Other rules in Marathon County
Compare Marathon County to another location·View the Wisconsin building safety overview
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