Short answer
A hardwired, interconnected smoke alarm system runs on the home's power with a battery backup, and when one alarm senses smoke, every alarm sounds. Alarms belong in each bedroom, outside sleeping areas and on every level, and should be replaced about every 10 years. Select Electric installs and replaces smoke detectors and alarms for homes and businesses in Midland, Bay and Saginaw Counties.
Smoke alarms are cheap insurance that only works if they're in the right places, powered and still within their service life. Many homes have a mix: a few old hardwired alarms, some battery units added later, and none of them talking to each other.
Hardwired, Interconnected, Battery Backup
Hardwired
The alarm is powered by a household circuit, so it doesn't depend on someone remembering to change a battery.
Battery Backup
A battery keeps the alarm working during a power outage. Many newer alarms use a sealed battery designed to last the life of the unit.
Interconnected
All alarms are linked, so one alarm sounding sets them all off. This is required for new construction and is the biggest single improvement for most existing homes.
Ionization, Photoelectric and Combination Alarms
Ionization alarms respond quickly to fast, flaming fires. Photoelectric alarms respond faster to slow, smoldering fires, the kind that can start in upholstery or wiring while people sleep, and they cause fewer nuisance alarms from cooking. Many fire safety organizations recommend having both technologies, either with dual-sensor alarms or a mix. Photoelectric alarms are the usual choice near kitchens and bathrooms. Combination smoke and carbon monoxide alarms cover both hazards in one device.
Signs It's Time to Update
- Your alarms are more than 10 years old, or have no date at all.
- Bedrooms don't have their own alarms.
- Alarms aren't interconnected, or you have a mix of brands that won't link.
- An alarm chirps even with a new battery, or goes off with no smoke. See smoke detector chirping or false alarms.
- You're finishing a basement, adding a bedroom, or remodeling, which often requires bringing alarms up to current code.
- You have fuel-burning appliances or an attached garage but no carbon monoxide alarms.
How the Job Goes
- Walk through the home or building. Where alarms are now, where they're needed, and what kind are installed.
- Plan. Locations, hardwired or wireless interconnection, and whether combination smoke and CO alarms make sense.
- Install. New boxes and cable where needed, alarms mounted away from kitchens, bathrooms and air vents that cause false alarms.
- Test. Every alarm is tested, and we confirm that one sets off the rest.
Alarm Installation for Businesses
For commercial and light industrial buildings, Select Electric also installs alarms. What a building needs depends on its use and size. Many commercial buildings need a fire alarm system with its own design and permit requirements. Tell us about your building and we'll talk through what applies.
What It Costs
This work is priced per job, because the building, the distances and what's already in the panel are different every time. Ask for a written quote that lists the materials and everything included. For what drives electrical prices in general, see what electrical work costs.
Local Detail: Older Homes and Propane Heat
Many homes in Bay City and Saginaw were built before 1960 (U.S. Census, American Community Survey 2020–2024), long before smoke alarms were required at all. Those homes often have alarms added one at a time, battery-only and not interconnected. Around Midland County, 16% of homes heat with propane, and fuel-burning heat of any kind is a good reason to add carbon monoxide alarms alongside smoke alarms. If you ever smell burning or see scorch marks, see burning smell, buzzing or a hot outlet.
To update your smoke alarms, call (989) 835-3587.
Common Questions
Where should smoke alarms go?
Current codes call for a smoke alarm inside each bedroom, outside each sleeping area (such as the hallway outside bedrooms), and on every level of the home, including the basement. In new construction and many remodels they must be hardwired and interconnected, so when one sounds, they all sound.
What does interconnected mean?
Interconnected alarms are linked, by a wire in the cable or wirelessly, so that smoke detected in one alarm sets off every alarm in the house. A fire in the basement then wakes people sleeping upstairs with the doors closed, which a single standalone alarm might not do.
Why is my hardwired smoke detector chirping?
Most often it is the backup battery getting low, or the alarm reaching the end of its service life. Smoke alarms are generally meant to be replaced about every 10 years; check the date on the back. If a chirp or false alarm continues after a new battery, see our page on smoke detector chirping or false alarms.
Do I need carbon monoxide alarms too?
If the home has any fuel-burning appliance (gas or propane furnace, water heater, range, fireplace) or an attached garage, carbon monoxide alarms are strongly recommended and are required in many situations, including new construction. Combination smoke and CO alarms are available.
Can hardwired alarms be added to an older house?
Yes. We can run new cable to alarm locations, or use alarms that interconnect wirelessly where fishing cable through finished walls isn't practical. Call (989) 835-3587 to talk through your home.