Sourdough Burning on Top but Raw on Bottom: Heat Distribution

Short answer: if your sourdough burns on top but stays raw on the bottom, the heat is concentrated above the loaf. Move to the middle rack, use a baking stone or steel underneath, and check that your oven's bottom element is firing.

What's happening

Your oven has two heat sources:

• Top heating element (broiler)
• Bottom heating element

In bake mode, the bottom element does most of the work, with occasional top firings to maintain temperature.

If the top of your bread burns but the bottom is undone:

• Top element is firing too much (broiler issue)
• OR your loaf is too close to the top
• OR the bottom isn't getting enough heat

The 4 fixes

1. Move to middle rack

The bottom rack puts the loaf close to the bottom element (good for bottom) but far from the top.

The top rack puts the loaf close to the top element (bad: burning) and far from the bottom (bad: raw).

Middle rack:

• Even radiant heat from above
• Even conducted heat from below
• Bread bakes evenly

This single change fixes most cases.

2. Add a baking stone or steel

Place a baking stone or steel on the rack below the loaf. This:

• Stores and re-radiates heat
• Buffers the bottom heat to keep it consistent
• Provides a hot surface for the bottom of the bread

For Dutch oven baking, the cast iron is the stone. For sheet-pan baking, add a stone or steel.

3. Check oven element

Some ovens have a worn bottom element that fires inconsistently. Tests:

• Preheat with the door open and observe (you can see the element glow red)
• If only the top element fires reliably, the bottom is failing
• Have the oven serviced

4. Use a Dutch oven correctly

In a Dutch oven, the lid traps heat above and below. If you've removed the lid too early:

• The top continues to bake (good)
• The bottom slows (loses Dutch oven heat retention)

Don't remove the lid before 18 minutes. After removal, finish the bake at 425–450°F (not 475°F+) to prevent top burning while the bottom catches up.

Cast iron Dutch oven specifics

Cast iron retains heat well. The bottom of the bread bakes against this hot surface for the entire bake.

If your Dutch oven loaf has a burnt top and pale bottom:

• The Dutch oven wasn't preheated enough
• Or it's not actually cast iron (some "Dutch ovens" are aluminum, less heat retentive)
• Preheat 60 min before loading

Convection makes it worse

Convection mode circulates hot air, which:

• Makes the top brown faster
• Can leave the bottom underdone (less radiant heat below)

For most sourdough bakes:

• Use bake mode (not convection)
• If you must use convection, drop temperature 25°F

Tin foil rescue

If you notice top burning mid-bake:

• Drape a piece of tin foil loosely over the loaf
• This blocks radiant heat from above
• Lets the bottom catch up

The bake might extend 10 minutes but the loaf will finish evenly.

A balanced bake recipe

For evenly-baked sourdough:

• Preheat oven to 500°F with Dutch oven on middle rack, 60 minutes
• Score, load, drop temperature to 475°F
• Bake covered 20 minutes
• Uncover, drop to 450°F
• Bake 22 minutes uncovered
• Lift loaf out of Dutch oven, place directly on rack
• Bake 5 minutes more

The final on-rack step crisps the bottom without further darkening the top.

Internal temperature is the truth

Use a probe thermometer to confirm doneness:

• 200°F internal: enriched dough done
• 205°F internal: lean dough done
• 210°F internal: whole grain done

If the top is dark but the internal temp is 195°F, the bread isn't done. Lower the temperature, cover with foil, finish baking.

Oven calibration

If you suspect your oven runs hot or cool:

• Use an oven thermometer for 1 week
• Note the discrepancy at 500°F
• Adjust dial to compensate (or recalibrate per oven manual)

Some ovens run 50°F hot. Setting 450°F gives you actual 500°F. Setting 500°F gives you 550°F (which burns).

Sheet pan baking specifics

If you bake on a sheet pan (no Dutch oven):

• Use a baking stone or steel under the sheet
• Steam tray at the bottom
• Middle rack
• Don't put sheet pan directly on bottom rack

The stone underneath provides bottom heat that the sheet pan alone can't.

A bake-by-temperature approach

To prevent burning regardless of recipe:

• Preheat to 500°F
• Drop to 475°F when loading (most bakes)
• Drop to 450°F at lid removal
• Drop to 425°F if needed for final 5 minutes

This stepped temperature reduction lets the bottom catch up without burning the top.

When the bottom is done but the top is raw

Reverse problem? Move the loaf one rack lower or use the broiler briefly to finish the top.

But for most home bakers, the top burns while the bottom under-bakes. The fixes above solve the common case.

A diagnostic bake

To test your oven:

• Preheat at 475°F, middle rack, 60 minutes
• Bake a 1kg sourdough boule
• Check at 35 minutes
• Note: top color, bottom color, internal temp

If the results are evenly browned: oven is fine. If the top is darker: move to middle-low rack next time. If the bottom is darker: move to middle-high rack next time.

After 2–3 bakes, you'll know your oven's quirks and can adjust permanently.