Are you hearing things going bump in the night? Perhaps you’re hearing scratching, scrabbling sounds and you aren’t sure where they’re coming from? Well, before you bring in a priest to perform an exorcism, it may be worth considering whether your chimney is the culprit.
Having a stove or open fire during the colder months of the year is one of life’s many pleasures. There’s no finer feeling when it’s cold and miserable outside, than getting cozy, throwing a log on the fire, and basking in its warmth as you watch the flames flicker majestically. As great as that is, though, it does require a fully working chimney, and that could be the issue.
Chimneys are an integral part of any fire or stove. They not only ensure the fire burns efficiently and puts out enough heat, they also help ensure that the fire burns safely and you needn’t worry about smoke inhalation, carbon monoxide poisoning, or other similar issues. If you hear your chimney making strange noises, there likely is a problem.
So, why does your chimney make strange noises? Here are a few possibilities.
The Weather
Starting off with one of the most likely culprits for a nosy chimney, we have Mother Nature herself.
If you can hear strange noises coming from your chimney, take a look out of the window and find out what the weather is doing. If it’s raining heavily for example, or hail stoning, you could hear the rain/hail hitting your chimney cap or crown. The noise could be the droplets bouncing off it.
Another possibility is the wind. If it’s particularly windy outside, as the wind strikes your chimney, it could cause it to move, contract, or shake, which in turn will make an unusual, slightly unsettling noise. The best way to reduce wind-related chimney noise is to have a wind-resistant chimney cap or crown fitted.
Even the temperature can cause strange noises. In very cold weather for example, building materials can contract. As it warms up, they expand and can make creaking noises. If water gets into the brickwork or mortar and freezes, as it expands, it can cause chips and breaks. The noise you hear could be the masonry on your chimney chipping off.
Creosote Contraction and Expansion
Creosote is a natural by-product of burning a fire, and while natural, it’s something you need to control and keep a very close eye on.
Creosote is a tar-like byproduct of burning a fire that is found in smoke. As a fire burns and the smoke rises, the creosote sticks to the walls and lining of your chimney, creating a black layer of soot. The more you burn, the thicker the layer of creosote gets.
If a fire has been left for a while, perhaps over the spring and summer months, if you haven’t had the creosote removed, once you light the fire the layers of creosote could expand and contract as the temperature drops. This can cause cracking, creaking, popping, even snapping noises.
These noises aren’t just annoying, they’re a warning that your chimney needs sweeping. Creosote sticks to the chimney and builds up. It is also flammable. Too much of it can increase your risk of a chimney fire, which could be devastating. Try to get your chimney swept once per year, ideally before the winter.
Backdraft
If you hear a sudden roaring sound coming from your chimney, perhaps like very strong wind or even like an engine, backdraft, or drafts, could be responsible.
Backdrafts can happen when air is suddenly sucked down your chimney and into your fireplace. They often occur due to changes in air pressure. Backdrafts can be dangerous as they can cause smoke, carbon, carbon monoxide, and other toxic gasses to be blown down your chimney and into your home via your fire.
A chimney that fails to draw properly is often a primary cause of backdrafts, which is another reason to get your chimney swept regularly. You should also only burn fully seasoned wood. Burning green wood with a high moisture content creates too much smoke and not enough heat, making it very dangerous.
Structural Issues
If you can hear any audible clanging, banging, creaking, or breaking sounds, this could be down to structural issues affecting your chimney and/or the surrounding areas. If any parts of your chimney are unsecured, or have come loose, they may make a noise, especially in the wind.
Loose flashing, dampers, caps, or crowns for example, may all come loose and could make a noise in the wind. Fortunately, if they have come loose, there is an easy fix, which is simply to secure them in place.
As a house settles, chimneys may also move and cause a creaking sound. If this is particularly loud, your home’s foundations may be the issue and will need looking at in more detail.
Water
Water and fire do not get well together, and they’re two things you wouldn’t expect to find together either. If you do however, there could be a problem.
Chimneys are constantly exposed to the elements, and they can sometimes allow some rain to get inside. The idea behind chimney crowns and caps however, is to significantly reduce this. If your chimney is letting too much rain in, it too can cause unusual sounds to emanate from your fire.
If you can hear a hissing or cracking sound, water could have become trapped under a layer of creosote. As you burn the fire and the chimney heats up, the hissing sound could be the sound of the water evaporating and turning to steam. The cracking sound could be the creosote and rain mixture cracking in the heat.
The easiest way to resolve this issue is to ensure your chimney has been weatherproofed.
Animals or Insects
Finally, if you can hear strange or unusual sounds coming from chimney, animals or insects could be responsible.
If you can hear scratching, scrabbing, or unusual banging noises coming from up in your chimney, there may be animals inside. Birds can sometimes get stuck inside or choose to make nests at the top of your chimney, perhaps within the crown. Insects may also choose the inside of your chimney to make a nest.
Regular chimney inspections will ensure your chimney remains free of animals. Chimney covers are also useful for this very same reason. If you do find evidence of creatures inside, or if you suspect there may be, they will need to be removed by a professional safely right away.
