You shape the loaf carefully, score the top, and place it in the oven expecting the cut to open beautifully. Instead, the loaf stays almost closed along the score and tears near the bottom. Sometimes the split appears along one side; sometimes it runs beneath the loaf like an unwanted second score.

This usually happens because pressure builds inside the dough faster than it can escape through the intended opening. The expanding gases will always search for the weakest place. If the score cannot open easily, the loaf creates its own escape route—often close to the base.

Underproofing is one of the most common reasons a loaf tears at the bottom.

Dough that has not completed its final proof still contains a great deal of fermentation potential. Once it enters the hot oven, the gases expand rapidly and the yeast becomes very active for a short time. The loaf rises forcefully, but its outer surface may not stretch quickly enough.

An underproofed loaf often feels firm and tight before baking. When pressed gently, the indentation springs back almost immediately. In the oven, it may produce strong oven spring, but the shape becomes uneven and the crumb can contain large tunnels surrounded by tighter areas.

Give the shaped dough more time before baking. The exact proofing time will depend on dough temperature, room temperature, starter strength, and the amount of starter in the recipe. Watch the dough rather than relying only on the clock.

A score is not merely decorative. It creates a controlled weak point where the loaf can expand.

If the cut is too short, too shallow, or made with a dull blade, the surface may seal before the loaf has finished rising. The pressure then moves downward and breaks through the softer area near the base.

For a round loaf, one confident curved or straight cut is often enough. An oval loaf usually needs a longer score that follows its length. The blade should move quickly and cleanly without dragging the dough.

Very deep scoring is not always better. A deep cut can weaken the loaf and cause it to spread. The goal is to cut through the taut outer skin and give the expanding dough a clear path—not to divide the loaf.

When shaped dough is left uncovered, its surface gradually forms a dry skin. That skin becomes less flexible and may resist expansion in the oven.

Even a well-placed score can struggle to open if the surrounding dough has become dry and stiff. Meanwhile, the base of the loaf often remains softer because it was resting in a proofing basket or against a cloth. This makes the bottom edge an easier place for the pressure to escape.

Cover the dough during its final proof. A reusable cover, plastic bag, or well-sealed container helps prevent excessive drying. A lightly floured surface is fine, but it should not feel hard or leathery before baking.

The base of the loaf is usually where the shaping seam is located. If the seam is loose, covered with too much flour, or not pinched closed, it can open in the oven.

This is especially common when a heavily floured bench prevents the layers of dough from sticking together during shaping. The loaf may look smooth from above while the underside contains a weak line ready to split.

Use enough flour to prevent serious sticking, but keep the inside folds relatively clean. When you finish shaping, check the seam and close any obvious gaps before placing the dough in the basket.

Place the loaf seam-side up in the banneton if you plan to turn it out and score the smooth side before baking.

Steam keeps the surface of the loaf flexible during the first stage of baking. Without enough steam, the crust can set too early, trapping the expansion inside.

A covered Dutch oven naturally holds moisture released by the dough. When baking on a stone or steel, steam must be created separately. It should be present at the beginning of baking, not added after the crust has already formed.

At the same time, the baking surface must be properly preheated. A cold stone or tray may slow the setting of the base while the top begins to firm, contributing to uneven expansion. Preheat the oven and baking surface thoroughly before loading the loaf.

The position of the tear can help identify the problem.

A split directly along the bottom seam often points to weak sealing during shaping. A tear that runs around the lower side of the loaf is more often connected with underproofing, insufficient scoring, or a surface that dried during proofing.

If the loaf tears at the bottom but still has a dense crumb, it probably needed a longer final proof. If the crumb looks good but the score barely opened, look more closely at scoring depth, steam, and surface drying.

One loaf may not provide the entire answer. Notice whether the same split appears every time and change only one part of the process during the next bake.

A bottom split does not mean that the dough was bad. In many cases, the loaf simply had plenty of energy but nowhere suitable to release it.

Allow the shaped dough to proof sufficiently, protect its surface from drying, seal the shaping seam, and make a clean score immediately before baking. With good steam and a properly heated oven, the loaf can expand through the opening you created instead of breaking unpredictably near the base.

The goal is not to prevent expansion. It is to guide it.