Smoke Detectors: Madison vs Sun Prairie
How do smoke detectors rules compare between Madison, WI and Sun Prairie, WI?
Madison and Sun Prairie have similar restriction levels.
Madison, WI
Dane County
Madison enforces WI Stat 101.145 requiring smoke alarms on every floor and in every sleeping room of residential dwellings. Rental properties must have interconnected alarms verified at each tenant turnover under MGO 27.05.
View full Madison rules →Sun Prairie, WI
Dane County
Smoke detector requirements in unincorporated Dane County are set by Wisconsin state law, not the county. Wis. Stat. §101.645 requires functional smoke detectors in the basement and on every floor level (except attic/storage) of one- and two-family dwellings. New construction under Wis. Admin. Code SPS 321.09 must use hardwired, interconnected detectors inside each sleeping room and within 21 feet of sleeping-room doors. Violations carry up to $50/day forfeiture.
View full Sun Prairie rules →Key Facts Comparison
| Fact | Madison | Sun Prairie |
|---|---|---|
| State Law | WI Stat 101.145 | - |
| Location | Every floor and bedroom | - |
| CO Alarms | WI Stat 101.149 | - |
| Rentals | Checked at turnover | - |
| Free Program | MFD installs for eligible | - |
| 1-2 Family Statute | - | Wis. Stat. §101.645 |
| Multifamily/Lodging Statute | - | Wis. Stat. §101.145 |
| Required Locations | - | Basement + each floor level (except attic/garage/storage) |
| New Construction | - | Hardwired + interconnected per SPS 321.09 |
| Owner Repair Window | - | 5 days after written notice of non-functional alarm |
| Penalty | - | Up to $50/day forfeiture |
| County Add-Ons | - | None — state preemption |
Highlighted rows indicate differences between cities.
Madison FAQ
Can I use battery-only smoke alarms?
Existing dwellings can use battery units, but new construction requires hardwired interconnected alarms.
Does Madison Fire Department install alarms for free?
Yes. MFD provides free sealed 10-year alarms to income-qualified residents through a safety program.
Sun Prairie FAQ
Where am I required to install smoke detectors in my Dane County home?
Wis. Stat. §101.645 requires a functional smoke detector in the basement and on each floor level of your dwelling, except the attic, garage, or storage area. New construction under Wis. Admin. Code SPS 321.09 also requires alarms inside each sleeping room and within 21 feet of every sleeping-room door, hardwired and interconnected.
What is the penalty for missing or broken smoke detectors in Wisconsin?
Up to $50 for each day of violation under Wis. Stat. §101.645(4). If a tenant or inspector gives the owner written notice that an alarm is not functional, the owner has 5 days to fix it before the daily forfeiture applies.
Does Dane County require more than the state smoke detector rules?
No. Dane County does not layer additional smoke-alarm requirements on top of Wis. Stat. §§101.145 and 101.645 or Wis. Admin. Code SPS 321 for unincorporated areas. Town building inspectors enforce the state Uniform Dwelling Code at permit and final inspection.
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