By the Home Kiln Hub UK — Pottery Kiln Reviews, Guides & Buying Advice Team · Updated May 2026 · Independent, reader-supported

How Long Does a Pottery Kiln Firing Take? Bisque, Glaze & Raku Timings Explained

Pottery firing times are one of the most misunderstood aspects of home ceramics. You'll hear wildly different answers depending on who you ask—partly because the answer genuinely depends on your kiln size, type, and firing temperature. There's no single number that applies across the board.

The honest answer: bisque firing typically takes 8–15 hours from cold to temperature, glaze firing takes 6–12 hours, and the cooling phase adds another 24–72 hours before you can safely open the kiln. But those ranges hide important detail. Understanding the breakdown—and the factors that shift your actual times—helps you plan production, manage studio time, and avoid common mistakes like opening kilns too early.

Bisque Firing Times: First Fire

Bisque is the first firing that converts clay body to ceramic. For a home studio, expect these ballpark figures:

Small kilns (under 100 litres capacity) 6–10 hours to peak temperature (around 1000°C). These units heat quickly because there's less mass to bring up. A typical small electric kiln sitting in your studio might reach temperature in 8 hours on a standard firing schedule.

Medium kilns (100–300 litres) 8–15 hours to peak. This is the workhorse range for serious home potters. Load density matters here—a tightly packed kiln takes longer than a sparse one because the heat has to work through the pieces.

Large kilns (300+ litres) 12–18 hours to peak. At this scale, you're often running on a slow ramp specifically because rapid heating risks cracking shelves and causing uneven firing.

The actual schedule you use matters more than kiln size. A fast bisque schedule might reach temperature in 6–8 hours but risks thermal shock. A slow schedule spreads the rise over 12–18 hours and gives the kiln interior time to heat evenly. Most potters use medium schedules that balance safety and productivity.

One detail people miss: hold time. Many kilns add 30–60 minutes at peak temperature to ensure even oxidation throughout the load. That time doesn't cook anything further—it just lets the kiln stabilize. If you've never checked your kiln's schedule, you might not realise this pause exists.

Glaze Firing Times: Second Fire

Glaze firing is typically hotter (1200–1280°C depending on your glazes) but often faster than bisque because bisque ware conducts heat more efficiently than raw clay.

Small kilns 5–9 hours to peak.

Medium kilns 7–12 hours to peak.

Large kilns 10–16 hours to peak.

Glaze firing schedules are usually steeper than bisque—potters want to push the temperature quickly without overfiring the glazes. The trade-off is that you need a well-functioning kiln controller to manage this accurately. Manual pyrometric cones (those little clay pieces that bend at temperature) still work, but they're blunt instruments for precise glaze results.

A common mistake: assuming one kiln will fire the same way every time. In reality, kiln shelf age, element wear, and loading patterns shift firing curves slightly. Experienced potters keep firing notes for exactly this reason—what worked last month might need tweaking this month.

Raku Firing (Where Applicable)

Raku is specialist work—suitable only for certain clay bodies and glazes. If you're using raku:

You're looking at 2–4 hours total, including the reduction phase (pulling hot ware and smothering it in combustible material). This is intentionally fast and dramatic. Raku creates the crackle effects and metallic surfaces that make it visually distinctive. It's not faster because it's easier; it's faster because the firing itself is doing something different.

Raku also requires proper ventilation and safety equipment because the reduction phase produces smoke. It's viable for home studios but needs dedicated planning.

The Cooling Phase: Why It Matters

Here's where many home potters underestimate time. Cooling is not optional or negotiable—it's part of the firing.

After your kiln reaches temperature and hold completes, the heating elements shut off. The kiln then cools naturally:

• First 12 hours: fast cooling from peak down to around 600°C. This is when the kiln sheds most of its heat.
• Second 12–24 hours: slower cooling from 600°C down to around 200°C. This is critical for glaze maturing and for preventing thermal shock in your pieces.
• Final 12–48 hours: slow decline to room temperature. You can technically open many kilns around the 48-hour mark if you're patient, but waiting longer is safer.

Opening a kiln too early is a common cause of crazing (fine cracks in the glaze), dunting (sudden cracking of ware), and damaged shelves. The cooling phase isn't wasted time—it's when the chemistry finishes.

Some kilns have fans or forced cooling options. These speed the process but introduce their own risks if you're not careful. Most home potters let kilns cool naturally.

Why Kiln Controller Quality Shifts Your Timeline

A basic kiln controller manages temperature rise using a thermocouple and heating elements. A quality digital controller gives you precise ramp rates (say, 100°C per hour from 0–600°C, then 60°C per hour from 600–1280°C).

This matters because:

• Consistent results: Your glazes mature properly when temperatures rise predictably. Budget kilns with basic controls can overshoot or undershoot, requiring you to adjust schedules by trial and error.
• Faster troubleshooting: A digital controller with a memory function lets you review exactly what happened during the last firing. You can see if the kiln climbed too fast or held temperature unevenly.
• Time efficiency: You spend less time adjusting schedules if the kiln behaves consistently. Over a year of monthly firings, that's meaningful.

Basic mechanical timers and simple digital displays still work, but you're essentially guessing at ramp rates. For repeatable results, digital controllers with programmable schedules are worth the investment.

Real-World Timing Example

Here's what an actual studio day might look like with a medium-sized kiln:

Monday 9 a.m.: Load bisque and start 10-hour schedule to 1000°C with 1-hour hold. Monday 8 p.m.: Kiln reaches temperature, hold completes, cooling begins. Tuesday 8 p.m.: After 24 hours of cooling, it's cool enough to safely unload. Wednesday morning: Load the same ware for glaze, start 9-hour glaze schedule to 1240°C. Wednesday 6 p.m.: Glaze firing peaks, cooling begins. Thursday 6 p.m.: Safe to open after 24 hours.

So from raw clay to finished glaze ware is 48 hours of actual kiln time spread across five days. That's why production planning matters—you can't fire and sell in 24 hours.

Summary

Firing times aren't fixed—they depend on kiln size, load, schedule, and the cooling phase you can't skip. Bisque typically takes 8–15 hours to temperature, glaze takes 6–12 hours, and both require at least 24–48 hours cooling. Digital controllers reduce guesswork and give you consistent, repeatable results. Understanding these timelines helps you avoid costly mistakes and plan your studio around realistic cycles.