Carbon Monoxide Detector Requirements In Colorado (CO Detector)

Date Published: September 3, 2019

When buying or building a home, carbon monoxide detector requirements can get a little tricky. Each state has a slightly different code requirement, older houses and newer houses can have different needs, and there are rules on placement too!

But following these rules is very important because a CO detector can save your life. Roughly 400-500 people die every year from carbon monoxide poisoning, and over 50,000 people are sent to the hospital over it according to the CDC.

To prevent this issue, carbon monoxide detector requirements were created, and we are going to break them down below.

Graphic about co related deaths in the US. Carbon monoxide detector requirements can prevent this.

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What Are The Carbon Monoxide (CO) Detector Requirements In Colorado?

Short answer: You need them. 

Every house built in Colorado is required to have a CO detector.

As of July 1, 2009, Governor Bill Ritter signed into law Colorado House Bill 1091 which states that all dwellings that are built, rented, remodeled or sold must have a carbon monoxide detector installed.

This is required on all homes that have a fossil fuel burning device for heat, a fireplace of any kind, or an attached garage.

All of these configurations can generate carbon monoxide which can escape into the home if not properly mitigated. So it is very important to keep your CO detectors in place and in working condition.

The only exception to this rule is in multi-family properties where there may be a global fire alarm and CO detection system in place. If this is the case, your HOA/property management company will need to follow their own guidelines.

If you are buying a home and have a home inspection performed through Scott Home Inspection, we call out missing detectors and state that they are required to be installed. By Colorado law, the seller must install the units before the sale is completed.

If you are moving into a brand new home, the builder will be required to install CO detectors, and they will be checked for during their “certificate of occupancy” inspection.

Where Do I Place the Detectors?

Colorado Law states that the detectors need to be placed within 15 feet of all sleeping rooms.

If all the bedrooms in a home are located in the same hallway, only one detector is needed in the hallway. This can be a stand-alone unit or a combination with the smoke alarm.

Carbon monoxide detector requirements state that this is the only location necessary. However, this applies to all sleeping areas. So if you have bedrooms on every floor of your home, you will need a detector outside of each one.

Smoke and CO Detector Placement Floor Plan as state in the Boulder Rental License Requirements Carbon Monoxide detector requirements in colorado

One common misconception is that you need a detector on every floor. This is not the case unless there is a bedroom on each floor as well.

Another common place we see additional CO detectors is in a home’s utility room.

This is a best practice that we also recommend that people do. It is a good idea to place a detector close to the most common source.

However, this location is not required in Colorado law and you cannot force a seller to install a unit here.