How Long Does It Take to Fire Pottery in a Kiln?

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If you’re new to pottery, you might assume that firing a piece simply means putting it in the kiln, turning it on, waiting a few hours, and taking it out.

It’s not quite that simple.

A pottery firing can take many hours to heat up, followed by several more hours of cooling before the kiln is safe to open. Depending on the clay, firing temperature, kiln size, firing schedule, and amount of pottery inside, the entire process can easily take most of a day or even longer.

So why does it take so long?

Let’s break it down.

How Long Does a Pottery Firing Take?

There isn’t one universal firing time.

A typical firing might take roughly 8–12 hours to reach its target temperature, followed by another several hours of cooling.

For example, Skutt gives an example of a Cone 04 bisque firing taking about 12 hours to reach temperature and another 12 hours to cool, depending on the kiln size. Its example Cone 06 glaze firing takes about 8 hours to reach temperature and another 12 hours to cool.

Those are examples rather than fixed rules.

A different kiln, firing program, clay body, or kiln load can produce a different result.

Stage 1: Preparing and Loading the Kiln

Before the firing even starts, your pottery needs to be ready.

For a first firing, the clay needs to be thoroughly dry.

This matters because leftover moisture can turn into steam as the kiln heats. If moisture escapes too quickly, it can damage pottery.

Some modern kiln controllers therefore include a preheat function that gently warms the pottery before the main firing begins.

Once everything is properly loaded, the firing can begin.

Stage 2: Heating Up

This is the longest active part of the firing.

The kiln gradually increases in temperature rather than immediately jumping to its maximum temperature.

That’s important because clay goes through several changes as it heats.

If pottery is heated too quickly, especially if pieces are thick or contain residual moisture, cracking or other problems can occur.

Skutt’s firing guidance provides different heating speeds, with slower programs intended for situations such as thicker or larger pieces.

A typical firing might therefore spend many hours gradually moving from room temperature toward the target temperature.

Why Can’t You Just Heat the Kiln Faster?

Because pottery isn’t simply a block of material sitting in an oven.

As the temperature rises, the clay undergoes physical and chemical changes.

Water needs to leave the clay, organic material burns away, and eventually the clay and glaze undergo the transformations that give fired pottery its final properties.

Going too quickly through certain stages can increase the risk of problems.

That’s why a carefully controlled firing is usually more important than simply trying to reach the highest temperature as quickly as possible.

Stage 3: Reaching the Target Temperature

Eventually, the kiln reaches the temperature required for the particular firing.

But temperature isn’t the only thing that matters.

Ceramic firing also involves heatwork, which is essentially the combined effect of temperature and time.

This is one reason pottery firing is often described using cones rather than temperature alone.

Skutt explains that firing more slowly can achieve the same amount of heatwork at a somewhat lower peak temperature, while faster firing requires a higher peak temperature.

For beginners, you don’t need to get deep into the science.

Just remember:

The kiln isn’t simply trying to reach a number. The pottery needs to receive the appropriate amount of heat over time.

Stage 4: Soaking or Holding

Sometimes a firing program includes a hold, also called a soak, at or near the target temperature.

This means the kiln maintains the temperature for a set amount of time instead of immediately beginning the next stage.

Why?

One reason is to help the temperature and heatwork become more even throughout the kiln.

For example, pottery in one area of a heavily loaded kiln may take longer to reach the same heatwork as pottery elsewhere.

Skutt explains that a short hold can help the kiln chamber “balance out.” It notes that holds of around 5–15 minutes can sometimes be useful, although the appropriate hold depends on the firing.

A hold isn’t automatically necessary for every firing.

It should be based on the clay, glaze, firing schedule, and kiln.

Stage 5: The Kiln Turns Off

Once the firing program is complete, the heating elements switch off.

But that doesn’t mean your pottery is ready to remove.

The kiln is still extremely hot.

In fact, this is where the second major part of the process begins:

cooling.

Stage 6: Cooling Down

Cooling can take almost as long as heating in some situations.

Skutt’s example firing schedules show approximately 12 hours of cooling for certain bisque and glaze firings, although actual cooling time varies with kiln size, insulation, load, and other conditions.

Large, well-insulated kilns can retain heat for a surprisingly long time.

That’s why you shouldn’t plan your firing around the moment the kiln reaches its target temperature.

The kiln still needs time to cool to a safe temperature.

Why Can’t You Just Open the Kiln?

Because pottery can be damaged by sudden temperature changes.

Opening the kiln while everything inside is still extremely hot can create thermal stress and increase the risk of cracking.

The safest approach is to follow the kiln manufacturer’s instructions and allow the kiln to cool appropriately before opening it.

In other words:

The firing isn’t finished just because the heating elements have switched off.

Bisque Firing vs. Glaze Firing

The timing can also depend on which type of firing you’re doing.

Bisque Firing

Bisque firing is the first major firing.

It transforms the dried clay into a hard ceramic material that can be handled and glazed.

Skutt gives a typical example of a Cone 04 bisque firing taking approximately 12 hours to reach temperature, followed by around 12 hours of cooling, depending on the kiln.

Glaze Firing

Glaze firing happens after the pottery has been bisque fired and glazed.

The glaze melts and develops into the finished surface during this firing.

Skutt gives an example of a Cone 06 glaze firing taking approximately 8 hours to reach temperature, followed by around 12 hours of cooling.

Again, these are examples rather than universal firing times.

What Can Make a Firing Take Longer?

Several things can affect firing time.

Kiln Size

A larger kiln can take longer to heat and cool than a smaller kiln.

How Full the Kiln Is

The amount of material inside the kiln affects the firing.

A heavily loaded kiln can behave differently from a lightly loaded kiln.

Thickness of the Pottery

Thick pieces often need slower firing schedules than thin pieces.

Skutt specifically recommends slower firing for larger or thicker-walled pieces.

Target Temperature

A low-fire firing generally doesn’t require the same peak temperature as a high-fire stoneware or porcelain firing.

Higher-temperature firings can therefore take longer.

Kiln Condition

Heating elements, insulation, electrical supply, and other equipment factors can influence how efficiently a kiln reaches its programmed temperatures.

Firing Program

A slow firing will naturally take longer than a faster program.

The firing schedule should be appropriate for the pottery rather than chosen simply to save time.

So, How Long Should You Expect?

For a beginner, a useful rule of thumb is to think in terms of a full day rather than a few hours.

A firing might spend around 8–12 hours heating, followed by another 8–12+ hours cooling, depending on the firing and kiln.

Some firings can be shorter, while others can take considerably longer.

Orton’s controller documentation, for example, lists approximate firing times of 3–5 hours for certain low-fire programs, 6–8 hours for mid-fire programs, and 9–11 hours for high-fire programs, before accounting for the complete cooling period.

This is why potters often start a kiln firing and simply let it run while they get on with other things.

A Kiln Firing Is More Than “Heating Up”

When someone says, “I’m firing my pottery today,” they’re talking about an entire process.

It involves:

Preparing → Loading → Heating → Reaching the target temperature → Holding if needed → Cooling → Unloading

Each stage matters.

And that’s why pottery requires patience.

The kiln may take most of a day to complete its work, but the result is worth waiting for.

Final Thoughts

A pottery kiln firing isn’t a quick process.

Depending on the kiln, clay, glaze, firing temperature, load, and program, the heating stage can take several hours, while cooling can take many more.

For example, manufacturer guidance gives examples of around 8–12 hours of heating followed by roughly 12 hours of cooling for certain ceramic firings.

So if you’re planning to fire pottery, don’t think of it as a two- or three-hour job.

Think of it as a process that may occupy most of a day or more.

And remember: patience is part of pottery.