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📍 FREE GUIDE — UPDATED 2026

Where to Place CO Detectors
in Your Home

Placement determines whether your detector catches CO before you're exposed — or after. Most detectors are installed wrong. Here's the correct approach for every room, per UL 2034 and NFPA 720 standards.

⚠️ Most important rule: At minimum, install one detector on every floor of the home, including the basement, and one within 15 feet of every sleeping area. These two rules align with UL 2034 and are required by law in most states.

Room-by-Room Placement Guide

The guide below covers every location where CO detection is required or strongly recommended, per UL 2034 and NFPA 720 standards.

🛏️

Bedrooms

Detector required here
Where to place it
Within 15 feet of bedroom door, in the hallway outside
Mounting height
5–6 feet from floor, or on the ceiling
Avoid these locations
  • Inside a closed bedroom (impedes air circulation)
  • Behind furniture
  • In a corner where air is stagnant
Most CO deaths occur at night when victims are asleep and unable to recognize symptoms. Detectors must be close enough to wake sleeping occupants.
🚪

Hallways & Landings

Detector required here
Where to place it
Central hallway near sleeping areas; on each floor landing in multi-story homes
Mounting height
5–6 feet from floor (plug-in or wall-mount) or ceiling-mount
Avoid these locations
  • At the very end of a long hallway (poor circulation)
  • Near air vents that dilute CO readings
Hallways act as channels between rooms — a single well-placed hallway detector covers multiple bedrooms while ensuring alarm sound travels to all sleeping areas.
🛋️

Living & Family Rooms

Recommended if applicable
Where to place it
Near fuel-burning fireplace or gas heater; opposite side of room from vents
Mounting height
5 feet from floor or ceiling per manufacturer instructions
Avoid these locations
  • Directly above or below vents and drafts
  • Behind large furniture
  • Near exterior doors
Living rooms with gas fireplaces or space heaters are a common source of CO. A detector here provides early warning before CO migrates to sleeping areas.
🍳

Kitchen

Recommended if applicable
Where to place it
At least 15 feet from gas stove and oven to avoid nuisance alarms
Mounting height
5–6 feet from floor
Avoid these locations
  • Within 5 feet of stove or oven (false alarms from cooking)
  • Under the range hood
  • In a high-humidity corner near the dishwasher
Gas stoves produce brief CO bursts during ignition and cooking. Placement at distance prevents false alarms while still detecting dangerous levels from a malfunctioning appliance.
🏚️

Basement

Detector required here
Where to place it
Near the base of the stairs leading to living areas; near furnace or boiler
Mounting height
Ceiling or high on wall — CO is slightly lighter than air
Avoid these locations
  • Very high humidity areas (near sump pump, laundry)
  • Within 5 feet of furnace exhaust (false alarms)
  • Dead-air corners behind the water heater
Furnaces, boilers, and water heaters in basements are the #1 source of residential CO poisoning. A basement detector catches leaks before CO accumulates and rises to living areas.
🚗

Attached Garage

Detector required here
Where to place it
On the wall between garage and living space; near the ceiling on the garage side
Mounting height
6 feet from floor or ceiling-mounted
Avoid these locations
  • Very close to garage door opener (vibration damage)
  • Where vehicle exhaust blows directly on it
An attached garage is one of the highest CO-risk zones in any home. A car left running for as little as 2 minutes can fill a closed garage with lethal concentrations.
⛵

Boats & RVs

Detector required here
Where to place it
Each sleeping cabin; galley/kitchen area; near generator compartment
Mounting height
High on wall or ceiling — follow marine-rated manufacturer instructions
Avoid these locations
  • Locations exposed to spray or condensation without proper marine-rated unit
  • Near exhaust vents
Boats and RVs are enclosed spaces where generator and engine exhaust can accumulate rapidly. Generator exhaust on a nearby vessel can blow through an open porthole.

5 Universal Placement Rules

These apply regardless of room — follow them wherever you install a detector.

📐

One detector per floor, minimum

CO doesn't instantly fill an entire home — a detector on a different floor may not alarm until levels are dangerously high on your floor.

🛌

Within 15 ft of every sleeping area

This is the UL 2034 design standard. It ensures the alarm is loud enough to wake someone from deep sleep before dangerous exposure occurs.

🔌

Plug-in detectors: use permanent outlets

Don't use a plug-in detector in a location where the outlet might be needed or is regularly unplugged. Use a wall-mount or hardwired unit instead.

🌡️

Avoid extreme temperature ranges

Don't install in unheated outdoor structures, directly outside a hot oven, or where temps regularly exceed 90°F or drop below 40°F.

💨

Avoid high-airflow locations

Don't install directly under or above supply vents, near ceiling fans, or in drafty hallways near exterior doors — moving air dilutes CO readings.

Quick Reference Summary

Print this table and keep it with your home safety records.

Location Required? Height Key Rule
🛏️ Bedrooms Yes 5–6 feet from floor, or on the ceiling Within 15 feet of bedroom door, in the hallway outside
🚪 Hallways & Landings Yes 5–6 feet from floor (plug-in or wall-mount) or ceiling-mount Central hallway near sleeping areas; on each floor landing in multi-story homes
🛋️ Living & Family Rooms If present 5 feet from floor or ceiling per manufacturer instructions Near fuel-burning fireplace or gas heater; opposite side of room from vents
🍳 Kitchen If present 5–6 feet from floor At least 15 feet from gas stove and oven to avoid nuisance alarms
🏚️ Basement Yes Ceiling or high on wall — CO is slightly lighter than air Near the base of the stairs leading to living areas; near furnace or boiler
🚗 Attached Garage Yes 6 feet from floor or ceiling-mounted On the wall between garage and living space; near the ceiling on the garage side
⛵ Boats & RVs Yes High on wall or ceiling — follow marine-rated manufacturer instructions Each sleeping cabin; galley/kitchen area; near generator compartment

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Based on UL 2034 and NFPA 720 standards. Free to cite and share with attribution to AirShield (airshield.store).