Sourdough 102: Why Your Bread Looks Flat (and How to Fix It)

Introduction

You followed the steps.
You used good flour.
Your starter looked active.

But when the bread came out of the oven… it was flat.

If this sounds familiar, you’re not alone. Flat sourdough is one of the most common frustrations for bakers — and the good news is, it’s fixable.

In this guide, we’ll break down exactly why sourdough loaves turn out flat and how to correct each issue.

What Does “Flat” Mean?

A flat loaf usually means:

• Poor oven spring

• Low volume

• Spreading sideways instead of rising upward

This typically points to one core problem:
👉 Your dough didn’t have enough strength or energy to rise.

1. Weak or Underactive Starter

Your starter is the engine of your bread. If it’s not strong, your dough won’t rise properly.

Signs of a weak starter:

• Doesn’t double in size within 4–6 hours

• Few bubbles

• Smells dull or overly sour

How to fix it:

• Feed consistently (1:2:2 or 1:3:3 ratio)

• Use it at peak rise (not after it collapses)

• Keep it warm (around 75–78°F / 24–26°C)

💡 Tip: A strong starter should float in water and smell slightly sweet and tangy.

2. Under Fermentation

If your dough hasn’t fermented long enough, it won’t have enough gas inside to expand.

Signs:

• Tight crumb

• Dense loaf

• Little rise during baking

Fix:

• Extend bulk fermentation

• Look for:

  • 30–50% rise

  • Smooth, slightly jiggly dough

  • Visible bubbles

3. Over Fermentation

Yes — too much fermentation is just as bad.

Overproofed dough loses structure and collapses.

Signs:

• Dough spreads like pancake batter

• Very sticky and hard to shape

• No oven spring

Fix:

• Shorten bulk or final proof

• Use cooler temperatures

• Watch the dough — not the clock

4. Poor Shaping (Lack of Tension)

This is one of the most overlooked issues.

If you don’t create surface tension, your dough will spread instead of rising.

Signs:

• Dough flattens immediately after shaping

• No structure in the final loaf

Fix:

• Use firm, confident shaping

• Pull the dough tight against the surface

• Create a smooth, taut outer skin

💡 Think of it like wrapping the dough in tension — this helps it rise upward.

5. Too Much Hydration

High hydration doughs are beautiful — but harder to control.

If you’re still learning, this can cause flat loaves.

Fix:

• Reduce hydration slightly (e.g. from 80% → 70–72%)

• Build strength with stretch & folds

6. Weak Gluten Development

Without proper gluten structure, your dough can’t hold gas.

Fix:

• Perform 3–5 stretch and folds during bulk

• Mix thoroughly at the beginning

• Use strong bread flour

7. Steam & Oven Setup (Critical for Oven Spring)

Steam keeps the crust soft in the first minutes of baking, allowing the bread to expand.

Without proper steam → your loaf sets too early → no rise.

Common issues:

• Not enough steam

• Releasing steam too early

• Oven not hot enough

Fix:

• Preheat thoroughly (at least 45–60 minutes)

• Use strong initial steam

• Keep steam during the first 8–12 minutes

• Then release and finish baking dry

💡 In deck ovens or SBO setups, steam timing makes a huge difference in final volume.

8. Scoring Issues

Your score controls how the bread expands.

Problems:

• Too shallow → random bursting

• Too deep → collapse

• No angle → no ear, less lift

Fix:

• Score at a 30–45° angle

• Use a confident, clean cut

• Don’t hesitate

Putting It All Together

Flat sourdough is rarely just one mistake — it’s usually a combination.

The key is to focus on:

• Strong starter

• Proper fermentation

• Good shaping technique

• Correct steam and baking setup

Once these align, everything changes.

Final Thoughts

Sourdough teaches patience — and every “flat” loaf is part of the process.

At Dough’n Roll, we’ve baked thousands of loaves, and the difference always comes down to the same thing:

Time, technique, and attention to detail.

Master those, and your bread will rise — literally.