What You’ll Learn
- How over-fermentation causes spreading.
- How dough strength affects shape.
- Why high hydration can flatten a loaf.
- How shaping tension helps.
- How to distinguish fermentation from shaping problems.
Quick Answer
A flat sourdough loaf is commonly caused by over-fermentation, weak gluten development, too much hydration for the flour, or insufficient shaping tension. Check how the dough behaved before baking rather than focusing only on oven temperature.
This lesson is part of our Troubleshooting section: “Fix the most common sourdough problems.”
Over-Fermentation
Dough that has fermented too far often loses strength and spreads quickly.
Weak Gluten
If the dough never gained strength during mixing and folds, it may not support itself.
Hydration Too High
A wet dough can be beautiful when the flour and technique support it, but difficult when they do not.
Shaping Tension
Good shaping creates a taut outer skin without tearing the dough.
Proofing Basket Support
A correctly sized banneton helps the loaf maintain form before baking.
What Happens in the Oven
Poor oven spring may exaggerate a flat shape, but the cause often began earlier.
From Our Workshop
If the dough pours out of the banneton like batter, the problem is almost never the scoring blade.
Bake Slower Tip
Lower hydration slightly while you learn fermentation and shaping.
Common Mistake
Do not tighten an over-fermented dough aggressively. It usually tears rather than becoming stronger.
Today You Learned
- Over-fermentation often causes flat loaves.
- Weak gluten reduces structure.
- High hydration demands stronger technique.
- Shaping tension matters.
- The cause usually begins before baking.
Frequently Asked Questions
Can underproofed dough be flat?
Sometimes, but it more often springs unpredictably.
Why does the loaf spread after scoring?
The dough may be weak or overproofed.
Will a smaller banneton help?
Only if the current basket is oversized.
Does flour strength matter?
Yes.
Can I bake flat dough in a tin?
Yes, that can be a useful rescue.
Make the Next Bake Easier
Better dough strength and fermentation control matter more than trying to force height at the oven stage.
Continue Learning
Next lesson: Why Is My Sourdough Dough So Sticky?
Troubleshoot one variable at a time
Diagnose from the whole loaf, not one symptom. Compare dough strength, fermentation, proofing, scoring and bake together. Changing several stages at once can hide the real cause and make the next result harder to interpret.
