Tag: oven spring

High-Altitude Sourdough: Why Your Loaf Changed When You Moved Up the Mountain
You had it figured out. The recipe, the schedule, the way the dough felt under your hands, all of it dialed in after months of practice. Then you moved, or started baking at the cabin, and the very same loaf came out wrong. Flatter. Drier. Overblown and then collapsed. Nothing in your routine changed except one thing: your elevation.

If your sourdough suddenly misbehaves after a move up the mountain, you are not losing your touch. Altitude genuinely changes the physics of your dough, and once you understand what shifted, the fixes are simple and consistent. Let’s walk through what altitude actually does, from the cause you’ll feel first to the ones hiding in the background, and exactly how to adjust.

Same recipe, higher ground: altitude quietly rewrites how your dough behaves.

What high altitude actually changes

Three things shift as you climb, and they all trace back to one fact: the higher you go, the lower the air pressure.

First, lower pressure means gases expand more freely. The carbon dioxide your starter produces pushes against less resistance, so dough rises faster and further. Second, the air is usually much drier at elevation, so your dough and its surface lose moisture more quickly than they did at sea level. Third, water boils at a lower temperature, which subtly changes how heat and steam behave in your oven. Most home bakers feel these effects strongly starting around 3,000 feet, and they get more pronounced the higher you go. Let’s take them in the order they’ll bite you.

Cause one: everything ferments faster, so you overproof without noticing

This is the big one, and it’s almost always the first thing to go wrong. With less air pressure holding the dough back, fermentation gas expands more and your loaf races through bulk fermentation and the final proof. The schedule that gave you a perfect loaf at sea level now carries the dough right past its peak.

The flatter loaf on the right is the classic altitude tell: it proofed faster than you expected.

An overproofed loaf spreads instead of rising, tears raggedly, bakes dense and gummy, and loses its oven spring. If that sounds like your new altitude loaf, this is your culprit. The fix is to stop trusting the clock and start trusting the dough. Watch for the real signs that bulk fermentation is done, a 30 to 50 percent rise, a domed and jiggly surface, a few bubbles at the edges, rather than a set number of hours. You will likely find the dough is ready noticeably sooner than your old routine said.

You can also slow the whole process down to give yourself margin: use a little less starter in the dough, keep your fermentation space a touch cooler, or lean harder on a cold retard in the fridge. If you are still unsure which way your loaf failed, our guide to telling overproofed from underproofed sourdough will help you read the signs before you commit to a change.

Cause two: the dry air stiffens your dough

At elevation the air is thirsty. It pulls moisture out of your dough during mixing, folding, and shaping, and it dries the surface skin faster than you’re used to. The result is a dough that feels tighter and stiffer than the same recipe did at sea level, which can hold back the open, airy crumb you want and make shaping fight you.

Thinner air lets fermentation gases expand more, so everything moves faster up high.

The fix is usually a small bump in hydration. Try adding an extra two to four percent water to your recipe (for a loaf using 500 grams of flour, that’s roughly 10 to 20 grams more water) and see how the dough responds. Add it gradually; you want the dough supple, not soup. If the new wetter dough feels unmanageable at first, our tips for handling sticky, high-hydration dough will keep it from turning into a mess on the counter. Keeping your dough covered between steps matters more than ever up high, so the surface doesn’t dry into a tight skin that resists rising.

Cause three: wild oven spring, then a flat or collapsed loaf

Dry mountain air pulls moisture from the dough, so a touch more water often restores it.

Altitude can give you dramatic early oven spring, the dough leaps, because the gases inside expand so eagerly in the heat. That sounds great until the structure, already stretched thin by fast fermentation, can’t hold the expansion and the loaf collapses or spreads into a disc. A loaf that balloons and then falls, or simply bakes flat and wide, is telling you the gluten network gave out under pressure it wasn’t built to handle.

The answer is stronger structure and a slightly earlier bake. Build good tension when you shape, since a well-shaped, taut boule resists spreading far better than a slack one; if your loaves keep flattening, revisit how to fix a sourdough that spreads instead of rising tall. And because fermentation runs fast, aim to bake when the dough is a touch underproofed rather than perfectly proofed by sea-level standards. That extra reserve of strength gives the loaf something to push against in the oven instead of blowing out and deflating.

Cause four: the oven itself behaves differently

This one is subtle but worth knowing. Because water boils at a lower temperature at altitude, steam forms more readily and moisture escapes your loaf a little faster during the bake. In practice, two small adjustments help. Keep your Dutch oven covered or your steam in place for the full first phase so the crust stays flexible long enough to spring, then uncover and finish with a good dry, hot stretch to drive out the extra moisture and set a crust that lasts.

You generally do not need to crank the oven hotter; if anything, a very high elevation loaf can benefit from a slightly lower temperature and a minute or two longer, so the inside finishes before the crust over-darkens. Bake to a deep golden-brown and, if you use a thermometer, to an internal temperature around 205 to 210 degrees Fahrenheit (96 to 99 Celsius), regardless of what the clock says.

Your high-altitude adjustment cheat sheet

Pulling it together, here is where to start when you bring a sea-level recipe up the mountain. Change one or two things at a time so you can see what’s working:

Use a little less starter, or ferment a touch cooler, to slow things down. Judge bulk by the dough’s rise and feel, not the clock, and expect it to finish earlier than before. Add a small amount of extra water to counter the dry air, and keep the dough covered at every rest. Shape with real tension and bake slightly on the underproofed side to protect your oven spring. Keep it covered or steamed through the first phase, then finish dry and hot, baking to color and internal temperature rather than time.

Dial in the timing and even thin air gives you the spring you are chasing.

Putting it all together

A sourdough loaf that changed the day you changed elevation is not a broken recipe or a lost skill. The thin, dry mountain air simply speeds your fermentation, stiffens your dough, and super-charges your oven spring, so the schedule and hydration that were perfect lower down now need a nudge. Slow the ferment, read the dough instead of the clock, add a little water, build strong structure, and bake to color. Give it two or three bakes of small tweaks and your old loaf, the tall, open, crackling one, comes right back, thin air and all.

Want to watch these adjustments in real time, from reading a fast bulk ferment to shaping for spring? The full walkthrough lives on the LoafLovers YouTube channel, and our free sourdough troubleshooting guide covers overproofing, flat loaves, and dry dough in the same symptom-to-fix format. Your mountain kitchen isn’t working against you. It just needs a slightly different conversation with the same good dough.

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October 15, 2026
The Big Tunnel Under Your Sourdough Crust: What Causes a Hollow Flying Crust and How to Fix It
You pulled a beautiful loaf out of the oven. The crust is dark and blistered, it sang as it cooled, and you were already composing the photo. Then you cut into it and the knife drops through a dense slab of crumb into a giant hollow cavern right under the top crust. The crust has lifted off like a dome over an empty room. It is one of the most deflating moments in home baking, partly because the outside looked so promising.

Bakers call this a flying crust, or sometimes tunneling. It is not a random accident and it is not ruined bread — it toasts perfectly well. But it is a clear signal that something went wrong between the mixing bowl and the oven, and once you know how to read it, the fix is usually straightforward. Let’s work through the real causes, from most common to least, and exactly what to change for each.

What a flying crust actually is

During the first few minutes in a hot oven, your loaf does most of its expanding. The outside sets into a crust while the inside is still soft and full of gas that is rapidly expanding in the heat. In a healthy loaf, that expansion pushes the whole structure up evenly — the crumb and the crust rise together and stay fused.

A flying crust happens when the crust sets before the crumb underneath it has finished rising, or when there is already a large weak void sitting just below the surface. The top skin firms up, the gas below keeps expanding and pushing outward, and because the crumb can’t rise into the crust, it tears away instead. The gas collects in that gap, inflating it into the hollow dome you sliced into. In almost every case the root problem is one of two things: the dough was not ready, or the surface was too tight and too fast to set. Let’s separate them.

Cause #1: The loaf was underproofed

This is the single most common cause of a hollow under the crust, and it surprises people because underproofed dough feels so firm and promising when you load it. An underproofed loaf still has enormous rising energy left in it. When it hits the heat, it lunges upward all at once in a violent burst of oven spring. The crust can’t keep up, the dough tears internally, and the gas pools in one big cavity rather than distributing into an even crumb.

The giveaway: a flying crust from underproofing usually comes with a dense, tight crumb below the gap, sometimes with a compressed band near the bottom. The loaf looks like it tried to explode upward and left the lower half behind.

The fix: give the dough more time in bulk fermentation. Watch the dough, not the clock — it should grow by roughly 50 to 75 percent, feel jiggly and alive, and show bubbles along the sides and surface. Use the poke test to judge readiness before you ever shape or bake. A cool kitchen slows everything down, so if your dough has been sluggish, it almost certainly needs longer than your recipe’s stated time.

The poke test tells you whether the dough has fermented enough to avoid a hollow, underproofed bake.

Cause #2: Big gas pockets trapped during shaping

If you shape your loaf too gently and leave large bubbles trapped just under the surface, those bubbles become the seed of a tunnel. In the oven they expand faster than the surrounding crumb, merge together, and lift the crust clean off. You’ll often see this as a flying crust in a loaf that is otherwise well fermented — the crumb below is open and nice, there’s just a giant pocket up top.

The fix: degas more deliberately during pre-shaping. You are not trying to flatten the dough into a pancake, but you do want to pop the biggest bubbles and redistribute the gas evenly. When you do your pre-shape and bench rest, give the round a firm pat to release any balloon-sized pockets, then let it relax before the final shape. Even, small bubbles in, giant trapped voids out.

Cause #3: The surface tension was too loose — or too tight

Shaping is a balancing act, and both extremes can cause tunneling. If your final shape is too loose and slack, the dough skin is weak and the expanding gas finds the path of least resistance — straight up into a dome under the crust. If your shape is too tight, you create a drum-tight skin that sets instantly in the oven and refuses to let the crumb rise into it, which also forces a separation.

The fix: aim for a smooth, taut surface with real but not desperate tension. The dough should hold a round shape and have a tight skin you could bounce a crumb off, without you fighting it or tearing the surface. If you’re not confident here, our guide to shaping a boule with real tension walks through the hand motions that build an even skin — the same skin that rises with the crumb instead of flying off it.

Degassing and reshaping with real tension removes the large gas pockets that later balloon into a tunnel.

Cause #4: Slack, over-hydrated dough that can’t hold its structure

Very high-hydration dough is wonderful for an open crumb, but it is also more prone to flying crust, especially for newer bakers. A slack dough has less internal strength to resist the oven’s push, so the structure gives way at its weakest point — the thin layer just under the setting crust. Add a slightly under-developed gluten network on top of that, and you have a loaf primed to tunnel.

The fix: back the hydration down by five to ten percent while you dial in your process, and build more strength with an extra set or two of stretch-and-folds during bulk. You want the dough to pass a rough windowpane and to hold a defined edge when you turn it out. Once your shaping and proofing are reliable at a moderate hydration, you can push the water back up with far less risk of a cavern.

Cause #5: The crust set too fast — steam and scoring

Sometimes the dough is fine and the problem is purely in the bake. If the top of your loaf blasts to a hard crust in the first few minutes — too little steam, or a surface that dried out during a long uncovered proof — it locks into place before oven spring finishes, and the still-expanding crumb has nowhere to go but away from it.

Scoring matters here too. A single shallow score at a low angle gives the gas a deliberate place to escape and expand, so it vents through the ear instead of ballooning blindly under the crust. Too shallow, too timid, or no score at all, and the pressure has to find its own exit — often as a hollow dome or a blowout bursting from the side.

The fix: bake with plenty of steam for the first 20 minutes — a lidded Dutch oven is the easiest way to guarantee it — so the crust stays soft and extensible while the loaf is still rising. Score decisively with one confident slash at roughly a 30-degree angle to create a controlled weak point. A crust that stays pliable long enough will rise with the crumb and stay married to it.

A shallow, angled score gives trapped gas a controlled exit instead of ballooning under the crust.

How to diagnose your own loaf in 30 seconds

Next time you cut a flying crust, read the clues instead of guessing:
- Hollow dome plus a dense, tight crumb below? Underproofed. Ferment longer, judge by feel and the poke test.
- Hollow dome but a nice open crumb elsewhere? A trapped shaping bubble. Degas and reshape more deliberately.
- Loaf also spread wide and flat? Too little surface tension or dough too slack. Tighten the shape, lower hydration, build more strength.
- Great interior but a thick, hard, early-setting crust? A baking problem. More steam, a decisive score, don’t let the surface dry out.
Most flying crusts I see come down to the same quiet pair: a loaf shaped a touch too gently and baked a touch before it was truly ready. Fix those two and the crust stops flying. You’ll know you’ve cracked it when you slice in and the crust is pressed tight against an even crumb, no cavern, no slab — just bread all the way through.

Want to see exactly what a well-degassed shape and a proper score look like in real time? The full visual walkthrough of fixing a flying crust — shaping, poke test, and scoring — lives on the LoafLovers YouTube channel, and you can grab our free sourdough troubleshooting guide to keep the symptom-and-fix chart next to your bench. No perfect loaves, just the ones that finally stopped tunneling.

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October 10, 2026
How to Shape a Sourdough Boule With Real Tension (So It Rises Up, Not Out)
You did everything right. The starter was bubbly, the bulk ferment looked good, you scored a confident slash – and the loaf still baked into a flat, sad disc that spread sideways instead of rising up. Before you blame your starter or your flour, look at the step almost everyone rushes: shaping. More flat loaves are born on the shaping bench than anywhere else. The good news is that shaping is a skill, not a mystery, and once you understand the one thing it is actually trying to do – build surface tension – your loaves stop spreading and start standing tall.

Tension is a skin: drag the dough to tighten its surface until it holds a taut dome.

What surface tension actually is (and why it matters)

Sourdough dough is soft and extensible – left to its own devices, gravity wins and it flows outward into a puddle. Shaping fixes that by creating a taut, smooth skin around the outside of the dough, like the surface of a water balloon. That skin is surface tension, and it is what holds the dough in a tall, round shape while it proofs and, crucially, while it hits the heat of the oven.

Here is why it decides whether you rise up or out. When the loaf goes into a hot oven, the gases inside expand fast – that burst is oven spring. A well-tensioned skin resists and directs that expansion upward, giving you height and a clean ear. A slack, tension-less blob has nothing to push against, so the same gas just makes it flatten and sprawl. Same dough, same oven – the shaping is the difference between a proud boule and a frisbee.

Same dough, different shaping: slack and spreading on the left, tight and holding on the right.

Don’t skip the pre-shape

Most spreading loaves come from jumping straight to final shaping on a tired, sticky mass. The fix is a two-step approach, and the first step is the pre-shape. Once bulk fermentation is done, tip the dough out, and with a bench scraper and lightly floured hands, gently gather it into a loose round. You are not tightening hard here – just coaxing it into an organized ball with a bit of structure.

Then walk away for 20 to 30 minutes. This bench rest is not optional idle time; it lets the gluten relax so the dough becomes shapeable again instead of fighting you and tearing. A pre-shaped, rested round also has an organized structure that takes tension far better than a formless heap. Skip this step and even good final-shaping technique struggles.

Fold the edges into the center to build structure before you round and tighten the boule.

The final shape: building the tension

Now the part that actually builds the skin. Lightly flour the top of your rested round and flip it so the sticky underside faces up. Then:
- Fold it into a parcel. Stretch the bottom edge up and over to the center, then the two sides in, then roll the top down over everything – like wrapping a package. Each fold adds a layer of structure.
- Flip it seam-side down. Turn the parcel over so the smooth side is up and the seam is against the counter.
- Drag to tighten. Cup your hands around the far side of the dough and pull it toward you across a bare, unfloured patch of counter. The slight grip of the surface catches the bottom of the dough and stretches the top skin drum-tight. Rotate a quarter turn and drag again. Two or three passes is usually enough.
You will feel it change from a slack lump into a taut, smooth dome that holds its shape when you take your hands away. That resistance is the tension you were missing. Place it seam-side up in a floured banneton to proof.

A well-shaped boule sits up in the banneton with a taut, smooth surface – not a slumping puddle.

The two ways shaping goes wrong

Too little tension is the classic flat-loaf cause: you were too gentle, or you floured the counter so heavily the dough just slid without gripping. If your shaped round slumps and loses its dome within a minute of shaping, it needs more tension – drag it a few more passes on a clean, unfloured section. That flour-free patch is the single most overlooked trick; dough cannot grip against a bed of flour.

Too much tension is the opposite mistake and just as real. Drag aggressively and you will tear the surface skin – it goes from smooth to ragged and sticky, and a torn skin holds gas about as well as a popped balloon. If you see the surface breaking, stop; you have gone past taut into torn. The target is drum-tight and smooth, not shredded. This is the same balance you are chasing when you check gluten with the windowpane test – developed and strong, not overworked.

When the dough just won’t hold a shape

Sometimes the technique is fine and the dough still refuses to tighten. Two usual suspects. First, overproofing: dough that has fermented too far loses its structure and goes slack and sticky, and no amount of shaping will rescue tension it no longer has. If your dough is billowy, gassy, and tears easily, review overproofed versus underproofed dough and pull your bulk ferment sooner next time.

Second, very high hydration. Wetter dough is inherently slacker and harder to tension – not impossible, just less forgiving. If you are wrestling an 80%-plus dough, either dial the water back while you build the skill, or lean on the specific handling tricks for sticky, high-hydration dough. Master tension at a friendlier 70% first, then push the water up.

Real tension pays off in the oven: a loaf that springs up tall with a clean, open ear.

Tension is the fix for the flat loaf

If your loaves keep spreading, resist the urge to change five variables at once. Nail shaping first, because it is the most common and most fixable cause of a flat bake. A pre-shape, a proper bench rest, and a final shape that leaves the dough drum-tight will, on their own, turn a spreading disc into a boule that rises up with real height and a clean, open ear. It is the same dough you have always made – you are just finally giving it a skin to push against.

Want to see the drag-and-tighten motion in real time? It is far easier to copy than to read – the full shaping walkthrough lives on the LoafLovers YouTube channel, and you can grab our free sourdough troubleshooting guide, including a shaping checklist, when you join the email list. No hard sell, just the fixes that work.

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September 12, 2026
Why Won’t My Sourdough Get an Ear? Scoring and Oven Spring Fixes
You pull the loaf out, and the flavor is there, the crumb is fine – but the top is flat and closed, the score has healed over into a faint scar, and there is no ear. Just a rounded, sealed dome where you wanted that proud, curling ridge. It is one of the most disheartening finishes in sourdough, because the loaf looks like it gave up right at the finish line.

Here is the reassuring part: the ear is not luck, and it is not a fancy technique reserved for professionals. It is the visible result of a short chain of things going right. When there is no ear, one link in that chain broke – and every link is something you can control. Let us walk the chain from the symptom back to the cause.

What an Ear Actually Is – and Why It Matters

An ear is the raised, curled flap of crust that lifts up along your scoring line as the loaf expands in the oven. It forms because you gave the bread one deliberate weak point in an otherwise tight skin. As the dough surges upward in the first minutes of the bake – what bakers call oven spring – all that expansion escapes through the cut, peeling the crust back and setting it crisp before it can fall.

So an ear is really a report card. It tells you that your dough had gas left to give, that the surface was tight enough to force the expansion in one direction, and that your score and your steam let it happen. No ear means one of those was missing. Let us find which.

The Real Reasons Your Loaf Won’t Open Up

Four things create an ear, and any one of them failing will flatten it: the dough still has to be springy and not overproofed, the surface has to be under tension, the score has to be cut correctly, and the oven has to be hot and steamy. Chase them in that order, because a perfect score cannot rescue dough that has nothing left to give.

Cause 1: Your Dough Is Overproofed

This is the number one ear-killer, and it is the cruelest, because an overproofed loaf feels so promising in the bowl – puffy, alive, full. But if the dough has fermented too long, the yeast has already spent most of its gas and the gluten has gone slack and tired. There is simply no stored energy left for a violent rise in the oven, so the loaf just spreads and seals over instead of bursting upward.

The fix is to catch the dough earlier. Aim for the point where it has risen by roughly half to three-quarters, feels airy but still domed, and springs back slowly when poked – leaving a shallow dent that fills in gradually. If your finger leaves a dent that stays put and the dough sighs flat, you have gone too far. When in doubt, bake a touch early: a slightly underproofed loaf will still throw a dramatic ear, while an overproofed one never will.

Cause 2: Weak Dough With No Surface Tension

Even perfectly proofed dough will not open cleanly if its skin is loose. The ear needs a taut outer surface to push against – a drum, not a puddle. If your shaping leaves the dough slack and shapeless, the expansion has nowhere to concentrate and simply flows outward.

Two fixes work together here. First, build real strength during bulk fermentation with a few sets of stretch-and-folds so the dough holds its shape. Second, shape with intention: create tension across the surface by dragging the shaped round against the counter to tighten the skin, then proof it seam-side up in a banneton so that taut face becomes the top you score. A cold dough helps enormously too – which brings us to a trick that fixes several problems at once.

Cause 3: You Are Scoring It Wrong

This is where most bakers actually lose the ear, and it usually comes down to three habits.

The first is the angle. A vertical, straight-down cut opens into a valley, not an ear. To get a lifting flap you want a shallow angle – hold the blade at roughly 30 degrees to the surface and slice almost sideways, cutting under a thin lip of skin. That lip is what peels back and curls into the ear.

The second is depth and confidence. A timid, shallow scratch heals shut; a hesitant sawing motion drags and tears. You want one smooth, committed stroke about a quarter to half an inch deep, in a single pass. Use a genuinely sharp blade – a lame or a fresh razor, never a butter knife – so it glides instead of dragging the surface.

The third is temperature. Cold dough scores like a dream and warm, slack dough smears and sticks. Proof your shaped loaf in the fridge overnight and score it straight from the cold – the firm surface takes a clean, crisp cut and holds the shape of your lip until the oven sets it.

Cause 4: No Steam, or an Oven That Isn’t Hot Enough

You can do everything above perfectly and still lose the ear in a dry oven. Steam keeps the crust soft and flexible for the first crucial minutes, buying time for the loaf to expand and the ear to peel up before the surface hardens. Without it, the crust sets almost instantly – locking the loaf shut like glue and choking off the spring.

The simplest reliable fix is a preheated Dutch oven: it traps the loaf’s own moisture into a private steam chamber. Preheat it hard, get the dough in fast, and keep the lid on for the first 20 minutes or so, then remove it to color the crust. And genuinely preheat – a fully hot oven (usually around 230 to 250C, 450 to 480F) delivers the initial blast of heat that drives oven spring. A lukewarm oven gives a lazy, ear-less rise.

A Repeatable Routine That Gets an Ear

Put the chain together and it becomes a checklist you can trust. Build dough strength with stretch-and-folds. Catch the proof a little early rather than late. Shape tight for a taut skin, then cold-proof overnight. Score the cold loaf in one confident stroke, blade held low at about 30 degrees. Bake in a ripping-hot, preheated Dutch oven with the lid on to trap steam. Miss the ear? Walk back through those five steps in order and one of them will be the culprit – almost always the proof or the scoring angle.

An ear is not the point of good bread – a tender, open crumb and honest flavor matter far more. But it is one of the clearest signals that your whole process came together, and chasing it will quietly make you a better baker at every step. If you want to see the scoring angle and the confident single stroke in motion – because this really is easier to watch than to read – the full technique lives on the LoafLovers YouTube channel, and you can grab our free sourdough troubleshooting guide to keep the whole chain on hand for your next bake. Cut with confidence, and let that loaf open up.

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August 14, 2026
Why Is My Sourdough Flat? Fixing Loaves That Spread Instead of Rising Tall
You slid the dough into the oven hoping for a tall, domed loaf with a bold ear – and twenty minutes later you’re looking at something low, wide, and spread out like a frisbee. No lift, no drama, just a sad puck of bread. It’s one of the most deflating moments in sourdough, and if you’re standing at the oven door right now wondering what went wrong, take a breath. A flat loaf is not a mystery. It’s a symptom, and it almost always points to one of a handful of specific causes.

The trick is that several different problems all end in the same flat result, so the fix depends entirely on which one bit you this time. Let’s read the clues on the loaf in front of you and match them to the real cause – then fix it for good.

Same recipe, two outcomes: a flat spreader on the left, a tall loaf with real oven spring on the right.

What a Flat Loaf Is Actually Telling You

A loaf rises tall for two reasons working together: the dough holds a strong, gas-tight gluten structure, and that structure has enough tension to push up rather than out when it hits the heat. When a loaf spreads flat instead, one of those two things failed – the structure was too weak to hold the gas, or the tension that would have directed the rise upward was never there.

That splits every flat loaf into two families. In the first, the dough was over-fermented – it rose beautifully at some point, then the gluten broke down and could no longer hold its shape, so it slumped. In the second, the dough was structurally weak from the start – underdeveloped gluten, too much water for your skill level, a tired starter, or a slack shape – so it never had the backbone to rise in the first place. Knowing which family you’re in is the whole game.

How to Tell Which Problem Is Yours

Before you fix anything, diagnose it. Think back over the last few hours and answer these:
- How did the dough feel at shaping? Slack, sticky, and unwilling to hold a ball points to overproofing or too-high hydration. Firm and springy but flat anyway points to shaping or oven problems.
- Did it spread the moment you turned it out of the banneton? If it puddled outward before it ever saw heat, the structure was already gone – suspect over-fermentation, a weak starter, or a dough that was simply too wet and too warm.
- Did it hold its dome on the counter but refuse to spring in the oven? That’s a heat-and-steam problem, or a shape with too little tension to climb.
- What did it smell like? A sharp, boozy, acetone or nail-polish note means fermentation ran long. A mild, pleasant tang means fermentation was probably fine and the fault is elsewhere.
Hold those answers in mind. As we walk through each cause below, you’ll see your loaf in one of them.

A dough that puddles the moment it leaves the banneton has lost its structure before it ever reached the oven.

Cause 1: The Dough Overproofed

This is the single most common reason a loaf spreads. Overproofing – whether from an over-fermented bulk, a too-long final proof, or dough that sat somewhere too warm – means fermentation ran past the dough’s peak. The yeast kept producing acid and gas long after the gluten could cope, and the network that was holding everything taut slowly dissolved. By the time it hits the oven there’s no structure left to spring, so it flows outward instead of rising.

The tells: slack, sticky, hard-to-handle dough at shaping; a shaped loaf that flattens on the counter instead of holding its dome; little to no oven spring; and that sharp, boozy smell. A poke test seals it – if you press a floured finger in and the dent stays put or the dough sighs and deflates, it’s overproofed.

The fix: shorten fermentation and watch the dough, not the clock. Most home bakers over-ferment because they trust a recipe’s “bulk for 4 hours” in a kitchen that’s warmer than the recipe assumed. End bulk when the dough has risen roughly 50-75% and looks domed, jiggly, and alive – not when the timer says so. Use an aliquot jar (a pinch of dough in a straight-sided jar, marked at the start) so you can read the rise precisely. And keep your dough cooler: warmth is the accelerator here, which brings us to the next culprit.

Cause 2: The Dough Was Too Warm

Temperature is the throttle on your entire bake, and a warm kitchen is the quiet reason so many loaves overproof without the baker realizing it. Dough ferments dramatically faster as it warms – a batch at 26 C / 78 F can be racing through bulk while the recipe was written for a calm 22 C / 72 F. You follow the times exactly and still end up past peak, because your kitchen was running hot the whole time.

The fix: take your dough’s actual temperature with a probe thermometer and aim for a target dough temperature around 24-25 C / 75-77 F. If your kitchen runs warm, use cooler water when mixing, shorten the bulk, and lean on the fridge for the final proof. Cold, slow fermentation is far more forgiving – it widens the window where the dough is perfectly ready, so you’re less likely to blow past it.

Cause 3: A Weak or Under-Strength Starter

If your dough never really came alive – sluggish bulk, barely any rise, dense and flat at the same time – look at your starter before you blame your technique. A young, neglected, or under-fed starter simply can’t generate the gas and acidity a loaf needs, and no amount of good shaping will save a dough that had a weak engine.

A strong starter at peak – domed, bubbly, and lively – is the engine behind a tall loaf.

The fix: feed your starter on a reliable schedule and only bake when it’s at peak – domed, bubbly, and roughly doubled within 4-8 hours of feeding. The float test is a quick confidence check: a spoonful that floats in water is full of gas and ready to work. If yours is sluggish, give it a few days of consistent feedings (try 1:2:2 or 1:3:3 starter-to-flour-to-water by weight) somewhere warm before your next bake. A strong starter is the cheapest upgrade to your bread there is.

Cause 4: Weak Gluten and Too-Slack Dough

Gluten is the scaffolding that traps gas and holds the loaf’s height. If it’s underdeveloped – not enough mixing, too few stretch-and-folds, or a flour too low in protein – the dough stays extensible and floppy instead of strong and elastic, and it spreads under its own weight. The same thing happens when the hydration is simply too high for your current skill level: a very wet dough can make a gorgeous open crumb in experienced hands, but for many bakers it just puddles.

The fix: build more strength and, if you’re struggling, take some water out. Give the dough a proper set of stretch-and-folds or coil folds during bulk – usually three or four sets in the first couple of hours – until it feels smooth, tight, and holds its shape. Do a windowpane check: stretch a small piece thin; if it goes translucent without tearing, your gluten is there. And there’s no shame in dropping hydration. If your recipe calls for 80% and you’re fighting a soupy mess, come down to 68-72% until you’re consistently getting tall loaves, then climb back up. A strong dough at lower hydration beats a slack one at high hydration every time.

Cause 5: Not Enough Shaping Tension

Even a perfectly fermented, well-developed dough will spread if you shape it loosely. Shaping is where you build the taut outer skin that holds the loaf together and directs the oven spring upward instead of outward. Skip that tension and the dough has nothing to climb.

Shaping is where you build the taut skin that holds the loaf tall – drag and cup until the surface tightens.

The fix: shape with intent. After a gentle pre-shape, let the dough rest 20-30 minutes so it relaxes, then do a final shape where you build real surface tension – fold the dough over itself and drag the taut ball across an unfloured patch of counter, cupping your hands around it so friction tightens the skin. You want to feel it firm up under your hands. A well-shaped loaf should sit up as a proud, tight round or oval, not sag. This one habit rescues more flat loaves than any other single change.

Cause 6: A Cold Oven and No Steam

Sometimes the dough was fine and the oven let you down. Oven spring – that final dramatic rise in the first ten minutes – depends on two things: intense heat that sets the crust fast enough to trap the rise, and steam that keeps the crust soft and stretchy long enough for the loaf to expand before it hardens. Bake in a cool oven or a dry one, and the crust sets too soon, the loaf can’t push up, and it settles wide.

Trapped steam plus a screaming-hot start is what turns a good dough into a tall, blistered loaf.

The fix: preheat hard and trap steam. Get your oven fully up to temperature – usually 230-250 C / 450-480 F – and preheat a Dutch oven or baking stone inside it for a good 45 minutes so it’s genuinely screaming hot when the dough goes in. The easiest way to guarantee steam is to bake in a covered Dutch oven for the first 20 minutes; the loaf steams itself in its own moisture, then you remove the lid to brown and crisp. If you bake on a stone, add steam with a preheated tray of water or a few ice cubes. Hot start, trapped steam, tall loaf.

Your Next-Bake Fix List

Put it together and the flat loaf stops being a mystery. Next time, run down this short list: bake with a starter at peak; keep your dough temperature around 24-25 C and end bulk by rise, not by clock; develop the gluten until it passes the windowpane and drop hydration if you’re fighting the dough; shape with real surface tension; and load it into a screaming-hot, steamy oven. Change one thing at a time so you learn which lever mattered for your kitchen, and you’ll watch the loaves climb.

Want to see the shaping tension, the poke test, and a proper Dutch-oven load in real time? The full fix – with close-ups of every step – lives on the LoafLovers YouTube channel. And if you’d like a one-page cheat sheet to keep by the oven, grab our free sourdough troubleshooting guide when you join the email list. No hard sell, just the answers for your next bake.

Sources & further reading:
- The Perfect Loaf – Why Is My Sourdough Bread Flat?
- King Arthur Baking – Sourdough Troubleshooting
Related: Why Is My Sourdough Gummy? The Real Causes of a Dense, Underbaked Crumb (and How to Fix It)

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August 11, 2026