9 Warning Signs Your Chimney Needs Cleaning


If your home has a chimney, it’s vitally important to have it inspected and cleaned on a regular basis. But what are the signs that a chimney needs cleaning?

Warning signs that your chimney needs cleaning are poor airflow, blockages from birds and animal nests, difficulty lighting or maintaining a fire, smoke not rising up the chimney, oily spots on fireplace walls, bad odors, and a build-up of creosote or soot that is falling from your chimney.

I’ll now walk you through the nine warnings signs in-depth so that you can prevent a fire hazard in your precious home.

1. Insufficient airflow up the chimney

There should always be a good flow of air in a chimney. If the damper is open, you should be able to feel air rising up even when there is no fire lit. If you can’t feel any air flowing at all, especially if it’s a windy day, then it’s a good sign that your chimney needs cleaning.

2. Difficulty starting a fire

If there isn’t enough oxygen coming from your chimney, then it can often be difficult to get your fire to start as wood needs oxygen to burn. Therefore, if you’re having problems lighting your fire, then your chimney could need cleaning.

3. Fire doesn’t burn well

If you’re able to light a fire but find that it doesn’t burn properly, then this could be another sign that your fire isn’t getting enough oxygen for it to burn properly. This could be because the chimney is blocked or there is a problem with the fireplace damper.

4. Birds or animals in the chimney

One of the most common issues with chimneys is animals nesting in them. Birds often nest in the top of chimneys and cover the vents, and small animals such as squirrels sometimes make nests in chimneys. These nests can be a problem as they compromise the airflow of your chimney and risk catching fire when you have the fire lit.

5. Oily spots on fireplace walls

Black, oily spots on the walls of your fireplace are a pretty good indicator that your chimney needs to be cleaned. These spots are creosote, which is a thick substance that will build up in your chimney all the way to the top and can restrict the airflow. A reduction in airflow will cause your fire to burn irregularly and not as hot.

6. Bad odors

Just like the oily spots on the wall of your fireplace, a smell similar to that of a campfire coming from your fireplace indicates that creosote has built up in your chimney. It’s important to have your fireplace cleaned if this is the case as creosote can easily catch fire and ruin your home and possessions, not to mention risk your life.

7. Smoke not rising up the chimney

One of the most tell-tale signs that your chimney is blocked is smoke not rising up the chimney as it should. This is often caused by creosote restricting the airflow.

8. Build-up of creosote on the chimney damper

Often, black creosote can build up on your chimney’s damper and if that happens, your chimney probably needs cleaning.

9. Soot falling from the chimney

Soot or creosote falling out of your chimney is another tell-tale sign that your chimney needs cleaning. Falling soot and creosote are often caused by a build-up of creosote in the chimney.

All of these signs are pretty easy to notice, and you should always take action once you spot even one of them to ensure the safety of yourself and your home.

You can call an inspector out to check that your chimney is up to code and safe to use, and you can call a chimney sweep out for a thorough cleaning.

When do I need a chimney inspection?

There are a few occasions when it is absolutely imperative that you arrange for your chimney to be inspected straight away as delays could result in a serious loss of damage to your home.

You should always arrange an inspection if you have just bought the house, haven’t used the chimney in a long time, or if you notice any of the nine signs listed above.

When you buy a new house, you probably won’t know when the chimney was last inspected, so it’s extremely important to arrange an inspection before you attempt to use the fireplace as many house fires are caused by a chimney that needed to be cleaned.

It’s also important to have the venting system checked if you have had any changes made to your heating system or if you’ve added a stove. An inspector will make sure that your chimney and all of the venting systems are up to code and in good working condition.

If your chimney hasn’t been in regular use, then there’s a likelihood that birds or other small animals could have nested inside, which can cause blockages.

Winter can often take its toll on a chimney, and there is the risk that the liner or masonry could have become damaged by moisture or the freeze-thaw action that usually occurs in the winter months.

Not only that, but any damage or normal deterioration that is not fixed straight away can lead to the problem getting worse the longer it is left. Therefore, it is not only safer to keep on top of any maintenance requirements, but it is cost-effective too.

How often should my chimney be cleaned?

Although it does depend on how often your fireplace is used, there are guidelines stating how often your chimney should be cleaned to ensure that it doesn’t become a fire hazard.

It is recommended by the National Fire Protection Association that chimneys, fireplaces, vents, and solid fuel-burning appliances be cleaned annually. The Chimney Safety Institute of America recommends that your chimney should be cleaned once there is 1/8″ (3mm) of soot build-up inside the chimney.

However, if there is any creosote build-up inside the chimney, it should be cleaned even if there is less than 1/8″ (3mm) of soot build-up.

Whenever there is a significant build-up of soot and creosote, there is a serious risk of a chimney fire. If that happens, then you can end up with a damaged chimney and even fire damage in your home or roof area.

Therefore, the chimney should always be cleaned regularly to reduce this risk. Also, always remember to have your furnace flue system cleaned as well.

Quite often, a fireplace that is used frequently will produce a lot of soot and creosote when it is cleaned and this should be fully removed to prevent the risk of a chimney fire.

When is the best time to clean my chimney?

You should always have your chimney cleaned before you need to use it, which will most likely be in the winter months as the cold weather sets in. Therefore, spring, summer, or early fall is a good time to have it done.

Thanks for reading!

Graham Walsh

I want to share everything I know about home improvement in order to help you. Whether you're a home enthusiast or an industry professional, I have the information that you need.

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