Key takeaways:
- Candle tunneling happens when the wax melts only in the center, leaving a ring of unmelted wax around the edges.
- Prevent tunneling by letting the wax melt all the way to the rim each time you burn it (especially the first burn), keeping the candle out of drafts, and trimming the wick to about ¼ inch.
- Fix tunneling by wrapping the top of the candle in foil to create a “heat dome” and burning until the surface evens out, or removing excess wax from the sides.
Candle tunneling happens when your candle burns straight down the middle, and the wax on the outside doesn’t melt.
The fastest way to fix candle tunneling is to trim the wick to about a quarter-inch segment, wrap aluminum foil around the top of the candle, and cut a hole big enough for the “tunnel” part of the candle (usually about 1 inch wide) to remain uncovered.
You can also try trimming the wick down and using your hair dryer (on the lowest setting) to slowly melt the outside edges of the candle to even out the wax.
Do your candles cave in when you burn them? This is one common issue we’ve seen countless times, and it never gets less annoying. This candle-lovers’ pet peeve is affectionately called tunneling.
Luckily, all Snif candles have gone through extensive wax and wick testing to an even burn when properly cared for.
For all the other candles (insert major side eye) out there, we have a solution to stop candle tunneling once and for all.
What Is Candle Tunneling?
Tunneling happens when only a small portion of the wax around the wick melts while your candle burns. It will sort of look like your candle is caving in on itself.
Candle tunneling is a problem for a few reasons.The uneven burn created by tunneling significantly shortens your candle’s life span. That’s because the tunnel will continue to burrow with each burn, leaving all of the nice-smelling, unreachable wax on the sides of your candle jar where it can’t be melted by your wick(s). Tunneling also has a snowball effect, creating a deeper tunnel with each burn if not corrected.
In this article we’ll lay down the basics for what causes tunneling, and then share some of our quick fixes to avoid tunneling once and for all.
What Causes Candle Tunneling?
Here are the top three reasons your candle istunneling.
You Aren’t Burning Your Candle Long Enough
The most likely culprit for a tunneling candle is a short burn time. You’ll want to let them burn for three to four hours to help the wax create an even pool around the candle’s perimeter, depending on the size of the candle.
The general rule of thumb is to burn a candle for one hour per every diameter inch. So, if your candle has a two-inch diameter, you should let it burn for at least two hours. (But more on that below!)
Trust us, we love to light a candle the instant we walk into any room, too, but it’s important to light your candle when you know you will have enough time to safely burn it for an extended period of time.
Candle tunneling worsens with each burn because of “wax memory”. No, not fondly reminiscing on your last visit to Madame Tussauds! Wax memory means wax that was recently melted takes less heat to re-melt after cooling. So, if you don’t give your candle enough time to melt its outer ring of wax, that inner ring will keep melting faster than the rest of the candle the next time you light it.
Your Wicks Need a Trim
We're not the only ones who can benefit from a little self-care: our candles need some TLC from time to time, too. One of the best ways to avoid tunneling is to occasionallytrim your wicks.
Un-trimmed wicks can cause plenty of issues, like black smoke stains on your candle jar or flames that are too tall. In this case, an un-trimmed wick can supply too much heat to the wax too quickly, causing an uneven burn.
Two Words: Bad Candles
While we’d love to say that all candles are created equal, that’s just not the case.
If you’re on top of your candle care game but just can’t get to the root of your tunneling issue, you might be dealing with a low-quality candle. Usually, cheaper candles are more prone to tunneling. This is one of the reasons it’s worth it to invest in a candle you can trust. At Snif, we’ve crafted our candles to burn as evenly as possible by using 100% cotton, as well as vegetable and soy wax.
Fix Candle Tunneling Forever: 3 Steps
So, you’ve learned what tunneling is. Now, onto how to fix it forever.
1. Trim Your Wicks
Show your wicks some love and give them a nice trim from time to time. They’ll thank you with a smooth, even candle burn.
If your candle wick is too long or crooked, it could be a contributor to tunneling and an overall uneven burn. So, if your wick doesn’t look right, give it a quick snip.
Trimming is always a good call, even if your candles aren’t tunneling. As a rule of thumb, trim a quarter-inch segment off your candle wicks after every four hours of burn time. If you trim your wick too short, it might not be able to generate enough heat to burn that outer ring of wax.
2. Use a Hair Dryer
With a little bit of patience, this method can help reverse tunneling before it gets any worse.
Turn your trusty hair dryer to its lowest setting. By sticking with low power, you’ll avoid splashing the candle wax around.
Next, gently run your hair dryer around the parts of your candle with unmelted wax build-up. After some time, you should see the wax begin to melt away from the sides as the surface of the candle begins to even out.
When the candle has a symmetrical shape again, you can power off the hair dryer. Let the candle completely cool and reset before lighting it, and you should be good to go.
3. Try the Aluminum Foil Method
Another way to reverse the effects of candle tunneling is to try the aluminum foil method.
Like all good hacks, it only requires one item that you likely already have at home: aluminum foil. Before you grab your foil, trim down the wick of your candle and remove any debris that has fallen inside the tunnel.
From there, cover the top of your candle entirely with aluminum foil, and cut a small opening in the center about one inch wide.
Once you’ve cut your foil, gently remove it — being careful not to tear it — and light the wick. Put the foil back on and allow your candle to burn for a few hours. If you notice that the flame goes out as soon as you put the foil on, then chances are the opening is too small and you need to make it a bit wider.
Alternatively, you can also wrap a large piece of foil around the sides of the candle, folding it at the top so that it sufficiently covers the candle but leaves space for the flame to burn.
After a few hours, you should notice that the surface of the wax has completely melted. This should create a smooth layer and get rid of the tunneling effect. Although you might be thrilled to have revived your candle and want to light it immediately, give the wax a day or so to harden completely. This way, you don’t risk it tunneling again.
4. Burn Your Candles Based on Diameter
Our last pro tip is more preventative, but good to know when you’re going to light that new candle you just bought.
This one is pretty simple: To keep your candle from tunneling and create an even burn, you should keep your candle lit based on the candle’s diameter measurement.
For example, if the diameter of your candle is four inches, you should keep it lit for about four hours. If it’s five inches, five hours, and two inches, two hours — you get the picture.
By letting your candle burn based on its diameter, you’ll avoid tunneling and extend the candle’s lifespan. Our candles are on the bigger side, so you can let them burn for much longer; each candle gives you over 50 hours of total burn time.
How To Prevent Candle Tunneling
You can prevent candle tunneling by following the first-burn rule. The first time you burn your candle, you should allow enough time for the entire surface of the candle to melt. This will help set the “memory” of the candle and prevent tunneling during future burns.
Generally speaking, you should plan to burn your candle, especially for the first time, for as many hours as there are inches in the diameter of the candle. For example, a three-inch candle would need to be burned for three hours.
After the first burn, it’s important to trim the wick down to ¼ inch. It’s also a good idea to always burn your candles away from drafts and to make sure you’re not burning them on uneven surfaces.
For wide candle jars, it can be helpful to look for candles that have multiple wicks to reduce the risk of tunneling.
Meet Your New Favorite Candles
Now that you know how to maintain tunnel-free candles, it’s time to add a new one to your collection.
We’ve crafted a collection of candles with irresistible fragrances that you can try before you buy. Order a sample of a candle that piques your interest, try it out at home, and buy the full-sized version if you love it.
Each of the candles in our collection has its own unique blend of scents, so it’s easy to find something that fits your vibe and your space. Plus, we make our candles with clean industry standards, paraffin-free, cruelty-free, and vegan.
They’ll burn for hours — especially with our tips to avoid tunneling!
FAQs
What is candle tunneling?
Candle tunneling happens when the center of the candle burns down, and a wax ring is left on the sides. You don’t want this to happen to your candles because it wastes wax and lessens the scent throw.
Does aluminum foil fix candle tunneling?
Yes. Making an aluminum foil collar with a small opening traps heat inside the candle jar, allowing the outer wax to melt. Once the candle's surface is level, you can remove the foil and use it normally.
How long should the first burn be?
The first burn should be roughly one hour per inch of diameter. Always wait for an edge-to-edge melt pool before extinguishing your candle, especially on the first burn.
What causes tunneling?
Short first burns, drafty spots, or an undersized wick relative to the amount of wax and size of the container can all cause tunneling. To prevent it, make sure to keep the wick at ~¼".
Sources:
What Is Self Care? | Everyday Health
How to Prevent Candle Tunneling | Scent Snob
Diameter Definition & Meaning | Merriam-Webster