Accessory Structures in Spring Hill, FL: What Residents Actually Need to Know

If you live in Spring Hill or are thinking about moving there, accessory structures are one of those things you probably won't think about until they affect you directly. Spring Hill has 5 specific rules on the books covering different aspects of accessory structures, and some of them might surprise you.

Shed Rules

Under Hernando County Ordinance 26-38 (2024), sheds with impervious roof coverings of 120 sq ft or less no longer require a zoning permit. The maximum allowable shed wall height is 8 ft (raised from 5 ft). Sheds must sit at least 5 ft from side and rear lot lines in residential districts (Hernando County Code Appendix A). Sheds may not function as dwelling or living space. Sheds with electrical, plumbing, or concrete work require separate building permits regardless of size. Florida Building Code applies for any shed over 600 sq ft.

Key details: Code Reference: Hernando County Code Appendix A; Ordinance 26-38 (2024). Permit-Exempt Size: ≤120 sq ft impervious roof (no utilities). Side / Rear Setback: 5 ft minimum (all residential districts). Max Wall Height: 8 ft (raised from 5 ft by Ord. 26-38). Front-Yard Placement: Prohibited (behind front building line).

Building without a required permit triggers a Hernando County Building Division stop-work order and double permit fees under Chapter 6 of the County Code. Setback or use violations are enforced by Hernando County Code Enforcement under Chapter 10 with notice of violation, civil fines up to $250/day first violation and $500/day for repeats (FS 162.09), and possible removal order through the Code Enforcement Special Magistrate.

Spring Hill is more permissive than most cities when it comes to shed rules. That said, there are still limits.

Garage Conversions

Converting a Spring Hill garage to habitable living space requires a building permit and electrical permit from the Hernando County Building Division under the Florida Building Code 7th Edition (change of occupancy from U to R-3). If the conversion adds a kitchen and separate entrance, it becomes an Accessory Dwelling Unit subject to Hernando County's strict ADU rules (attached only, 50% size cap, owner-occupied, no separate sale). The conversion may not reduce off-street parking below the minimum required for the dwelling.

Key details: Building Permit: Required (change of occupancy from U to R-3). Electrical Permit: Required for added wiring. Building Code: Florida Building Code 7th Edition (2020). ADU Trigger: Kitchen + separate entrance. ADU Size Cap: ≤50% of primary dwelling gross habitable sq ft.

Building without permits triggers a Hernando County Building Division stop-work order, double permit fees under Chapter 6 of the County Code, and possible removal order. Creating an unpermitted second dwelling unit (kitchen + separate entrance) without ADU approval is a zoning violation under Hernando County Code Chapter 10 with notice of violation, civil fines up to $250/day first violation and $500/day for repeats (FS 162.09), and a cease-occupancy order. Sale of a property with an unpermitted converted garage may trigger disclosure obligations under FS 689.25 and post-closing liability.

ADU Rules

Hernando County permits an Accessory Dwelling Unit (ADU) only as an attached addition to an owner-occupied single-family home — detached backyard cottages, guest houses, and tiny homes on the same lot are NOT permitted. The ADU is capped at 50% of the primary dwelling's gross habitable floor area, may have its own kitchen, bathroom, sleeping area, and laundry, and may not be sold separately. Maximum of 2 dwelling units per lot (primary + ADU). Florida has no statewide ADU mandate.

Key details: Code Reference: Hernando County Code Appendix A (ADU definition and standards). Attached / Detached: Attached only — detached ADUs PROHIBITED. Maximum Per Lot: 1 ADU (2 total dwelling units per lot). Size Cap: ≤ 50% of primary dwelling gross habitable sq ft. Owner-Occupancy: Required — principal home must be owner's primary residence.

Building or occupying an unpermitted detached dwelling unit on a Spring Hill lot is a zoning violation under Hernando County Code Chapter 10 with notice of violation, civil fines up to $250/day first violation and $500/day for repeats (FS 162.09), and a cease-occupancy order from Code Enforcement. Building without permits triggers a Hernando County Building Division stop-work order, double permit fees under Chapter 6 of the County Code, and possible removal order.

Compared to other cities, Spring Hill takes a harder line on adu rules. The enforcement and penalty structure reflects that.

Carport Rules

Hernando County Code Appendix A permits detached carports as accessory structures in residential districts with a minimum 5 ft setback from side and rear property lines. Attached carports must meet the principal building's yard setbacks for the district (typically 25 ft front, 10 ft side, 20 ft rear in R-1B). Carports require a building permit from the Hernando County Building Division for structural review under the Florida Building Code 7th Edition with engineered wind-uplift anchorage for Hernando County's 130-140 mph wind zone.

Key details: Code Reference: Hernando County Code Appendix A Articles II and IV. Detached Carport Side/Rear Setback: 5 ft minimum. Attached Carport Setbacks: Principal-building setbacks (R-1B: 25 ft front, 10 ft side, 20 ft rear). Pre-72-3 Lot Side/Rear: 7 ft side / 15 ft rear. Permit-Exempt Threshold: ≤5 ft height AND ≤40 sq ft.

Building without a required permit triggers a Hernando County Building Division stop-work order and double permit fees under Chapter 6. Setback violations are enforced by Hernando County Code Enforcement under Chapter 10 with notice of violation, civil fines up to $250/day first violation and $500/day for repeats (FS 162.09), and possible removal order through the Code Enforcement Special Magistrate. Carports built without engineered anchorage that fail in a hurricane may also create insurance, post-loss, and liability problems for the property owner.

Tiny Homes

A tiny home in Spring Hill on a permanent foundation is treated as either a single-family dwelling (must meet the underlying Hernando County residential district's minimum lot size, setbacks, and 600-900 sq ft minimum living area) or as an attached ADU under Hernando County's strict ADU rules (50% of primary, attached only, owner-occupied). Tiny homes on wheels (THOWs) registered as RVs or park-model trailers are NOT permitted as residences. HUD-Code manufactured homes are permitted only in the R-1MH Manufactured Home district.

Key details: Building Code: Florida Building Code 7th Edition (no Appendix Q). Tiny Home as Principal Dwelling: Permitted on permanent foundation if zone standards met. Min Living Area (R-1A): 600 sq ft. Min Living Area (R-1B, R-1C, R-2.5, RR): 900 sq ft. Tiny Home as ADU: Permitted only if ATTACHED (Hernando ADU rules).

Living in a THOW, RV, or park-model trailer in a Spring Hill residential district is a zoning violation under Hernando County Code Chapter 10 enforced with notice of violation, civil fines up to $250/day first violation and $500/day for repeats (FS 162.09), and an order to vacate from the Code Enforcement Special Magistrate. Site-built tiny homes built without permits trigger a Hernando County Building Division stop-work order, double permit fees, and possible removal order. Installing a HUD-Code manufactured home outside the R-1MH district is a separate violation.

This is one of the stricter rules in Spring Hill's municipal code. If you are unsure whether your situation complies, it is worth checking with the city before proceeding.

The Bottom Line

Spring Hill is tougher than many cities when it comes to accessory structures. Out of the 5 rules covered here, 2 are rated strict. If you are a homeowner, renter, or business owner in Spring Hill, take the time to understand these requirements before they become a problem. Most violations come with fines, and some repeat violations can escalate.

All of the above reflects Spring Hill's municipal code as of our last review. If you need specifics on fines, exemptions, or filing requirements, the detailed ordinance pages linked above have the full breakdown.