Candle Tunnelling: What It Is, Why It Happens, and How to Prevent It
Few things are as disappointing as lighting a beautiful new candle—only to find it burning straight down the middle, leaving thick walls of unused wax. This common phenomenon is called candle tunnelling, and the good news is that it’s avoidable (and sometimes even fixable).
What Is Candle Tunnelling?
Candle tunnelling happens when the flame burns a narrow hole down the center of the candle, leaving a ring of hard, unmelted wax around the edges. Not only does it waste wax, but it can also shorten the candle’s burn time and reduce fragrance throw.
Why Does Candle Tunnelling Happen?
Several factors can cause tunnelling:
- First burn mistakes – If the candle isn’t allowed to form a full melt pool the first time you light it, the wax will “remember” that burn pattern and continue tunnelling.
- Wick size – A wick that’s too small for the candle’s diameter won’t generate enough heat to melt the wax evenly.
- Drafty environment – Airflow from fans, windows, or vents can cause uneven burning.
- Poor wax quality – Some wax blends, especially very hard ones, may struggle to melt fully without the right wick.
How to Prevent Candle Tunnelling
1. The First Burn Is Crucial
When you light a candle for the first time, let it burn long enough for the melted wax pool to reach the edges of the container—usually 1–4 hours, depending on the candle size.
2. Trim the Wick
Keep the wick trimmed to about ¼ inch before each burn. This helps maintain a steady flame without producing too much soot or flickering.
3. Avoid Drafts
Burn your candle in a stable, draft-free location to ensure the flame heats the wax evenly.
4. Size Matters
For larger jars or pillar candles, make sure the wick is designed to handle the candle’s diameter. Multi-wick candles are often best for wide containers.
5. Rotate Your Candle
If your candle burns unevenly, gently rotate it every so often while lit to help heat distribute evenly.
Can You Fix a Tunnelled Candle?
Yes—often you can rescue it:
- Foil method: Wrap aluminum foil around the top of the candle, leaving an opening above the flame. The trapped heat will melt the leftover wax along the edges.
- Oven warm-up: Place the candle in a warm (but turned off) oven for a few minutes to soften and even out the surface.
- Heat gun or hair dryer: Melt the top layer of wax until smooth.
The Bottom Line
Candle tunnelling is more than just a cosmetic flaw—it’s wasted wax and lost scent. By giving your candle the right first burn, keeping the wick trimmed, and protecting it from drafts, you can enjoy a full, even burn every time.