Inside Every Bedroom
A smoke alarm on the ceiling of each sleeping room — doors close at night.
Home Safety Needs
Smoke & CO Detectors: They Expire Sooner Than You Think
Smoke and carbon monoxide detectors are life-safety devices with a limited lifespan — smoke alarms typically last about 10 years and CO detectors 5–7 — and they need testing and battery service on a regular schedule to actually protect your family.
Smoke & CO Alarm Placement
Where detectors belong in your home and garage
Two-Story Home With Attached Garage
REPLACE ON SCHEDULE
- Smoke alarms — every 10 years
- CO alarms — every 5–7 years
Batteries yearly, unless 10-yr sealed
Smoke alarm
Carbon monoxide alarm
Heat alarm (garage)
The Placement Rules
Outside Sleeping Areas
Smoke and CO alarms in the hallway serving the bedrooms.
Every Level
At least one smoke and one CO alarm per floor — basement included.
Kitchen Clearance
Keep smoke alarms at least 10 ft from cooking appliances to avoid false trips.
Garage & Entry
Heat alarm in the garage — not smoke — plus CO just inside the connecting door.
Test & Replace
Test monthly. Replace smoke alarms at 10 years, CO alarms at 5–7 years.
Does your home's coverage match these rules? Alarms are the one system you hope never runs — and Washington law requires working CO alarms in homes. One visit, and our licensed electricians walk every level, check the dates on every unit, and install hardwired, interconnected protection where it belongs.
Related: Smoke & CO detectors: they expire sooner than you think Smoke & CO detector installation & testing The codes we build to (WA CO-alarm law)
What to know
- Smoke detectors expire at roughly 10 years; CO detectors at 5–7 years — the sensors degrade even if the unit still chirps on test.
- Detectors need monthly test-button checks and battery changes on a regular schedule (or 10-year sealed batteries).
- Every bedroom, hallway outside sleeping areas, and every level of the home needs coverage; CO detectors belong near sleeping areas and fuel-burning appliances.
- Hardwired, interconnected alarms — when one sounds, they all sound — are the gold standard and required in new construction.
Why detectors expire
The sensing elements inside smoke and CO alarms degrade with age, dust, and humidity. An expired detector can still beep when you press the test button — the button tests the horn and battery, not the sensor. Check the manufacture date printed on the back: past 10 years for smoke (5–7 for CO), replace the unit, not just the battery.
The service schedule that keeps them working
Detectors are only reliable when they're maintained like the safety equipment they are.
- Monthly: press the test button on every unit.
- Twice a year: replace batteries (a good habit: when clocks change) unless the unit has a sealed 10-year battery.
- Yearly: vacuum dust from vents and verify every sleeping area and level is covered.
- At expiration: replace the whole unit — smoke at ~10 years, CO at 5–7 years.
CO risk is real in fuel-burning Puget Sound homes
Any home with a gas furnace, gas water heater, gas range, fireplace, or attached garage can produce carbon monoxide. CO is colorless and odorless; a detector is the only warning you get. Eco technicians check combustion safety during furnace and water-heater service, and our electricians install hardwired CO/smoke combination alarms where they protect best.
Upgrade to hardwired and interconnected
Battery-only alarms fail silently when batteries die. Hardwired detectors with battery backup, interconnected so every alarm in the house sounds together, give your family the earliest possible warning — especially important in multi-level homes where a basement alarm may not be heard in an upstairs bedroom.
Ready for the next step?
Talk to a licensed Eco pro — honest guidance and upfront pricing before any work begins.
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Common questions
How do I know if my detector is expired?
Look at the manufacture date printed on the back or side of the unit. Smoke alarms should be replaced about 10 years after that date, CO alarms after 5–7 years depending on the model — even if the test button still works.
Where should CO detectors go?
Outside every sleeping area, on every level of the home, and near (but not directly beside) fuel-burning appliances and attached garages. Follow the manufacturer's placement guidance — CO mixes with air, so wall or ceiling placement both work for most models.
Can Eco install hardwired interconnected alarms in an older home?
Yes. Our licensed electricians retrofit hardwired, interconnected smoke and CO alarms in existing homes, and wireless-interconnect models let us link alarms without opening every wall.
Questions? Talk to a real pro.
Licensed, insured, and bonded across the Puget Sound — upfront pricing before work begins.