Your loaf looked beautiful going into the oven—then it exploded out the side. Here's why that happens and what you can do about it.
A sourdough loaf often splits on the side when the dough expands during baking but the crust has not been given the right place to open.
Scoring, fermentation, dough strength and shaping can all influence where your loaf eventually bursts.
When bread goes into a hot oven, the gases inside the dough expand rapidly. The loaf needs a controlled weak point where that expansion can happen.
That's the job of scoring.
If your score is too shallow, positioned poorly, or doesn't provide enough room for expansion, the dough may find its own escape route.
Oven spring is the rapid expansion that happens during the early part of baking.
Heat causes gases to expand and fermentation continues briefly before the dough structure sets.
That sudden expansion is exactly why proper scoring matters.
Yes. Fermentation affects the structure and gas distribution of your dough.
If dough has not fermented sufficiently, it can behave differently during baking and may have less-developed structure and trapped gas distribution.
That doesn't mean every side split is caused by under-fermentation—but it's one of the variables worth examining when troubleshooting a loaf.
Shaping isn't just about making your loaf look pretty.
Good shaping helps create surface tension and organizes the dough structure. Poor or inconsistent shaping can affect how the loaf expands once it hits the oven.
Higher-hydration dough can be more challenging to handle and shape.
If you're still learning sourdough, a dough that is extremely wet can make every stage—from fermentation to shaping to scoring—more difficult to interpret.
Learning with a manageable dough can make troubleshooting much easier.
Instead of changing everything at once, work through the basics.
The side split is only one small part of understanding sourdough dough. Build your foundation with these Sourdough Academy resources.
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