Where is the best place to put my carbon monoxide detector?

Carbon Monoxide (CO) is a toxic gas that is both odourless and colourless. Therefore, the only way you’ll be able to identify its presence is by using a proven and respected carbon monoxide detector.

Why are carbon monoxide detectors so crucial for home safety? Well, because it is potentially lethal in confined and unventilated spaces. If a large amount of carbon monoxide is inhaled it will displace the oxygen in a person’s blood and ultimately deprive the heart, brain, and other vital organs the oxygen they need to function properly.

Carbon monoxide poisoning causes multiple deaths and hospitalisations every year worldwide.

In the UK alone, Department of Health and Social Care statistics show that carbon monoxide poisoning in homes is responsible for over 50 deaths and over 4,000 medical interventions each year.

Most of these could have been avoided if households have fitted a carbon monoxide detector. 

How is CO gas generated? 

Toxic carbon monoxide is produced when fuel is inefficiently burnt or not burnt properly. Fuel-burning appliances like gas boilers, gas fires and cookers are all potentially high-risk sources of CO if they are not maintained properly.

So, it’s vital that these appliances are checked regularly and serviced by qualified and registered engineers. It’s also imperative that for extra security a carbon monoxide detector is placed in the same location as these appliances.

Where is the optimum location to install a carbon monoxide detector?

Whether you choose to install just a single or multiple carbon monoxide detectors in your property, it is important to install each of them strategically.

You should install a carbon monoxide detector on on every level of your home including the basement and any attached garages. It is also advisable to install carbon monoxide detectors outside each bedroom or sleeping area, as the effects of carbon monoxide poisoning are almost impossible to detect when you’re asleep.

  • Before installation make sure the carbon monoxide detectors are Kite marked and meet all the stringent testing requirements of the region where the property is located. Make sure you also read the full manufacturer’s instructions before installation.

  • If you are unsure how to best install the CO detector, then ask a qualified engineer to do it for you.

  • Because carbon monoxide is slightly lighter than air and because it may be found with warm, rising air, detectors should be placed on a wall ideally about 5 feet above the floor, and preferably about 6 inches from the ceiling. You don’t have to fix the alarm to a wall directly, as it will happily work equally well if placed securely on a shelf. Detectors may be placed on the ceiling at a pinch, but never place the detector right next to or directly over a fireplace or flame-producing appliance.

  • Place carbon monoxide detectors at least 15 feet away from fuel burning appliances if possible: if not, place as far away as free space allows.

  • If your house has an attached garage, then place a CO detector within 10 feet of the connecting door to the garage.

  • If you are planning to install multiple carbon monoxide detectors on different floors, then ask an engineer to connect all devise together so that if one alarm sounds, they all sound.

What to avoid when installing carbon monoxide detectors?

Never place co detectors:

  • Near gas or fossil fuel appliances as these will likely lead to false CO detection and false alarms.

  • In humid areas of the house like bathrooms

  • In direct sunlight as this will cause it to overheat and malfunction

  • Within the direct reach of children or pets

  • Near windows or in draughty parts of the building

  • Behind doors, curtains or cabinets which will interfere with CO detection

Are CO detectors a legal requirement in all homes?

There is no legal requirement in the UK to install CO and smoke detectors in private homes, though common sense dictates that for the sake of safety this is the wisest thing to do in every home. In rented accommodation the situation is different.

On October 1st, 2015, new regulations came into force in England regarding the fitting of smoke and CO alarms in rented property. [Broadly similar rules apply in Scotland, though there are no formal regulations regarding carbon monoxide detectors in Wales and Northern Ireland, other than those written into the Building Regulations.] 

From this date, every private rented property needs to be fitted with smoke alarms and carbon monoxide alarms (if applicable). The requirement is to install at least one smoke alarm on every storey of the rental property on which there is a room used wholly or partly as living accommodation. The definition of room includes a bathroom or toilet. 

The regulations don’t say whether these alarms should be hard-wired or battery-powered. The regulations also don’t say anything about placement. Government guidance is to follow what the manufacturer recommends and that smoke alarms should normally be fitted to the ceiling in a circulation space – that is, on a landing or in a hallway.

Do you need a carbon monoxide detector if your home or garage has a gas boiler?

Gas boilers produce carbon monoxide gases naturally as part of the heating process.

However, this harmful gas is normally carried away from the home via a fitted air-tight flue.

It is none the less, still advisable to install a detector for peace of mind and protection if nothing else. If your home has an attached garage, then it is recommended that you fit an additional detector roughly 10 feet from the door linking the house to the garage.

If the garage is detached, then you will probably not need any additional carbon monoxide detectors.

Can you use a battery-powered carbon monoxide detectors in Vehicles?

Vehicle engines, like gas boilers, produce carbon monoxide. Under normal circumstances, the exhaust system of a vehicle is designed to prevent carbon monoxide seeping into the vehicle.

However, on occasion this system fails either because of a defective exhaust system or defective ventilation. Some smaller home CO battery-powered detectors might be suitable for use in a vehicle, but the alarm may well be too loud, and disconcerting should it activate.

However, there are some detectors on the market specifically designed for in-car usage. These are generally battery-operated, though models are available that can be plugged in via the car adapter. Such models will need to be linked to a mobile phone to operate effectively, however.

Do I need a CO detector if my home has a combi-boiler?

If your home has any fuel burning appliances, gas fires, gas boiler, furnace or combi-boiler, then yes, you are best advised to install a CO detector and a smoke alarm as well for the safety of you, your children and anyone else living in the property.

Do I need to install carbon monoxide detectors if my home is fitted with a multi-fuel stove?

The short answer to that is, yes, In the UK legislation dictates that if the multi-fuel stove was installed after October 2010, a CO detector is mandatory. If the multi-fuel stove was installed prior to this date there is legal compulsion to install a CO detector, but it is strongly advised none the less.

The CO detector must be installed in the same room as the stove and must be either on the ceiling and at least 300mm from any wall or on a wall, as high as possible and certainly above any doors or windows, but not within 150mm of the ceiling.

Whether on the ceiling or the wall, the horizontal distance between the carbon monoxide alarm unit and the stove should be between 1m and 3m.

Carbon Monoxide Detectors aftercare post-installation

  • After installing a Carbon Monoxide detector, test the appliance every month. Most detectors include a one-press test button designed to shine a light or sound an alarm that the detector is working perfectly.

  • Keep the detectors clean from dust and dirt for the optimum performance.

  • Always be vigilant for low battery alert warnings, and change batteries as soon as the warning alert sounds. Even if no alarm sounds, it is advisable to change the batteries at least once a year anyway.

  • Have an escape plan updated in case the alarm goes off. Carbon monoxide is lighter than air, so it rises. When the alarm goes off, crouch and stay low to the ground while making your way out of the building.

  • Inspect your ventilation systems. Carbon monoxide poisoning happens when there’s a build-up of the gas in an area. Making sure that all the areas in your home are well ventilated. This will drastically reduce the risk of carbon monoxide poisoning.


When searching for the origin of the name Alex, you will find that it comes from the Greek name Alexandros which means ‘protector.’ Perhaps that is why protecting and defending the home environment is so important to Alex, the author of this website. It is clear to see that Alex is very passionate about teaching others how to protect themselves and their loved ones from intruders. That can also be because, in ancient scriptures, the name Alex means ‘to assist other men’ by providing them the means for protection. But that is not all for this resourceful person who loves to write, which can be seen in the many articles found on this website. He aims to teach others how to protect their homes and share his wisdom with them through his articles. It is easy to put the face and the name behind this instructive and informative website when you look at it that way. Alex has come a long way in the home security industry, which is proven by the knowledgeable advice in his posts. His love for writing comes from his love for reading, which he has done in spades from a very young age. An insatiable desire to understand things has driven Alex throughout his years of growing up in a home where knowledge was appreciated. Not just knowledge but also the way it can be obtained, and that is through reading, which has been passed on to him. Alex believes that people should be encouraged to do what they want and need to in life to have a better and happier existence. His passionate way of living life can be seen in everything he does, especially in how he shares information with others. The reason and drive behind every tip and piece of advice on this website comes from a good place.

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