These Are The Reasons Why Your Candle Glass Cracked

Luxury candles are very expensive so nobody wants to deal with the following nightmare scenario.

You have a beautiful candle in a lovely glass container. Maybe it was a gift or you decided to treat yourself. It smells divine so you burn it all of the time. Then suddenly the glass cracks! 

But why has this happened? 

Let’s look at some of the reasons why this may have occurred and what you can do to reduce the chances of cracked candle glass. 

Check out our guide below. 

First off I would like to give give quick answer as to why a candle glass can crack.

So why do candle glasses sometimes crack? Put simply candle glasses can get very hot with all the melted wax pooled inside. These temperature changes can cause stress to the glass structure especially if it has a flaw or manufacturing fault. Often a cracked candle glass can be of no fault to the owner.

Extreme Heat

Broken candle with beautiful lights and reflections.

The main reason why cracked candle glass occurs is because of extreme heat. This may not come as a surprise because naked flames and molten wax produce scorching temperatures. 

Several factors will increase the likelihood of this happening. 

Firstly, if changes in the temperature are off-center, there is a greater risk of the heat being concentrated in one area. Naturally, this puts more pressure on the glass because it’s receiving an excessive amount of heat. 

Another common cause is a leaning wick. Try to adjust the wick before you light it so that it doesn’t lean to one side and focus its flame on one side with burning intensity. This will reduce the chance of cracked candle glass. 

Finally, splashing cold water can also lead to cracked candle glass because of temperature changes. Let’s look at that in more detail now. 

Flame too high

If you have not prepared your candle by cutting the wick to the desired length before use this can cause it to get to hot.

If the wick is too big it means that the wick will produce more heat when burning than is necessary, this can lead to the glass cracking.

For more information on flame High and candle maintenance please have a look at my guide

Temperature Changes 

Abrupt and stark temperature changes can lead to cracked candle glass. 

Some people put candles in the freezer because they believe that it will harden the wax. In theory, this melts slower and will last for longer. 

However, this isn’t a good idea if the candle is inside a glass container or receptacle. 

When you take it out of the freezer and light it, the heat will cause the candle wax to expand. This can cause irreparable damage if the glass is still very cold. 

Burning Too Long

It may seem counterintuitive but you shouldn’t allow your candle to burn for too long. 

The reason behind this is that the heat within the container will build up and accumulate. If there’s no way for it to escape then that is when the chances of cracked candle glass increase. 

If you want your candle to last for a long time, then don’t leave it burning all night. Enjoy it in smaller sessions than you would with regular tealights. If you don’t look after it, you won’t get the full value out of this luxury product. 

Is it Safe to Use a Cracked Candle Glass? 

In short, no it is not safe. Even if there’s just a hairline crack in the glass, it’s still not a good idea. As you continue to burn the candle, the chances of more damage will increase. 

Sure, it may be very tempting to use it if there’s just a thin line across the container. It probably still feels structurally sound when you pick it up. But there is a heightened chance of the crack expanding. 

This can lead to glass shattering and create a fire hazard. 

If the glass is fully broken, then avoid using the remains of the container. There’s a chance of you burning or even cutting yourself when you pick it up. Meanwhile, the hot wax may seep out of the receptacle. 

It also probably doesn’t even look nice anymore, so don’t the chance! 

Salvaging a Candle from Broken Glass

Cracked candle glass doesn’t mean your product is entirely useless. 

While you might not have a fancy container to put it in, there’s no reason why you can’t use your candle and enjoy its scent. Check out these easy methods to remove candle wax from a broken tub. 

  1. Freezing the Candle

Freezing the wax can be an effective way to retrieve it from cracked candle glass. Simply place the container in the freezer and leave it overnight. It’s wise to put it into a plastic bag so there’s less risk of losing glass shards in the freezer. 

The wax should harden and shrink, enabling you to scrape it out with a knife. If you’re lucky, it might even just fall straight out.

  1. Boiling Water

You can also use hot water to melt the wax and remove it from the cracked container. Of course, you need to use your discretion because it depends on the condition of the glass. 

Pour the boiling water inside, leaving some space at the top. The wax should melt and float to the top. After the water cools, you can remove the wax. Finally, pour the remaining water onto a strainer so that you can collect any leftover bits of wax. 

Your candle won’t be very pretty but you may be able to use the wax again. 

Have a read of my guide to 7 things that you can do with leftover wax for ideas to salvage your candle

Candle Safety Tips

There are some ways to reduce the chances of cracked candle glass and safety issues. 

It’s advisable to retire the candle when there is less than a quarter of the wax remaining in the container. The wax will burn with a higher intensity at the bottom of the container and increase the chance of cracked candle glass.

If you notice the flame touching the sides of the glass, you should extinguish it immediately. Adjust the wick before you use it again so that it doesn’t overheat the glass. 

While you shouldn’t allow your candle to burn forever, you do want it to form a complete wax pool. This will result in an even surface. If you blow it out before this, one side will be higher than the other and increase the likelihood of future issues.

Avoid lighting a candle in a drafty room because the candle is more likely to flicker. It’s not good for the flame to bounce off the sides of the container. 

Finally, don’t try to fix a broken candle jar. It’s better to throw out the entire product because it’s only going to end badly. Either remove the wax from the broken candle glass or buy a new one. 

Final Thoughts

Broken candle glass is irritating but it can be avoided if you take the necessary precautions. 

Read the label carefully and follow the manufacturer’s suggested burning practices. This will increase the lifespan of your candle. They’ll rarely say to burn for more than four hours.

If you do end up with broken candle glass, then it’s time to gauge the situation. If the damage is too severe, the safest bet is to just throw it out. This isn’t the happiest solution but it’s safest. 

There are methods to remove wax from broken glass but please exercise caution as you do so at your own risk. 

Andrew Scents and Aroma