Investor’s Guide to Sister Bay 4-Bedroom Limit STR Regulations
A common mistake new investors make in Sister Bay is assuming a large house means large income. You might buy a beautiful 5-bedroom waterfront home, only to discover your rental permit is limited to 8 people or fewer. This guide explains the difference between a home’s size and its legal rental occupancy, which is the key to maximizing your short-term rental (STR) income.
Sister Bay STR Rules: Navigating the 4-Bedroom Occupancy Limit
The Sister Bay 4-bedroom limit STR regulations are complex, and they rarely look at the number of bedrooms. They look at the septic system.
The Primary Constraint: Septic System Capacity
In Door County, the most critical factor for occupancy is the Private On-site Wastewater Treatment System (POWTS)—your septic system.
- The Math: Wisconsin law assigns occupancy limits based on the septic field size. In most residential areas, the standard is two people per bedroom but is capped by the system’s design capacity.
- The Problem: Many large homes built decades ago had smaller septic systems installed because they were only used by the owner’s family. A 5-bedroom home might only have a legal POWTS capacity for 4 bedrooms (8 people).
- The Risk: If you operate above the legal septic capacity, you violate both state and local sanitary codes. This can lead to fines and the revocation of your STR license.
Bedroom Count vs. Guest Occupancy
This is where the financial planning gets complicated.
| Home Size (Bedrooms) | Common STR Occupancy Cap | Key Factor Limiting Occupancy |
| 3 Bedrooms | 6 people | Typically straightforward if septic is modern. |
| 4 Bedrooms | 8 people | The standard legal maximum for many residential septic permits. |
| 5+ Bedrooms | Still Capped at 8 (or less) | Septic System Capacity (POWTS) is the immediate wall. You need proof of a larger system. |
The Conditional Use Permit (CUP) Hurdle
If you want to rent a large home to groups exceeding 8-10 people, you need a Conditional Use Permit (CUP) from the Village of Sister Bay.
- The Process: This involves a review by the Village Planning Commission. They look at parking, neighborhood density, and the certified capacity of your septic system.
- The Cost: Expect significant fees and public hearings, and there is no guarantee of approval.
Secondary Constraints: Parking and Noise
While the septic system is the primary financial constraint, the Village also heavily regulates guest behavior.
- Parking Limits: Most ordinances require at least two off-street parking spaces per STR unit. Large group rentals can trigger tighter limits to prevent vehicles from spilling onto public roads.
- Quiet Hours: Sister Bay strictly enforces quiet hours. Group rentals in large homes are highly visible, and neighbor complaints are the fastest way to lose your license.
Final Thoughts
The Sister Bay 4-bedroom limit STR regulations are really “septic capacity rules.” Do not buy a large investment home based on the number of beds. You must verify the legal septic capacity certified by the County Sanitarian.
Request a “POWTS Verification” Check
Before you close on a large STR home, we verify the hard numbers.
Request our Private Audit: “Sister Bay Occupancy & POWTS Verification.”
We will:
- Pull the official Door County POWTS permit for the property to see its certified capacity (e.g., 8 people).
- Cross-reference the capacity with the current Village of Sister Bay STR ordinance.
- Provide a Net Income Projection based on the legal occupancy limit, not the bedroom count.
Invest based on facts, not assumptions. Contact us today for your verification check.
Connect with Our Expertise
Use these guides to build your investment strategy.
- Investment Costs: STR Costs: What You Really Pay for Property Management in Door County
- Condo Inventory: The New Build Crunch: What to Know About Sister Bay’s Inventory Levels Right Now
- Waterfront Access: Ephraim private shoreline access rules
Further Resources
- Village of Sister Bay Short-Term Rental Ordinance:STR Ordinances – Village of Sister Bay
- This is the official page for the Village of Sister Bay’s short-term rental rules. It allows buyers to directly view the ordinances concerning licensing, parking, advertising, and the zoning amendments (which contain the four-bedroom limit and other specific occupancy and usage restrictions).