Choosing insulation

Brick & Insulation Energy Savings

  1. Top-loading kilns typically come with either 2-1/2" or 3" thick insulation.
  2. You will save energy with 3" brick (and have a stronger kiln).
  3. 3" brick will also slow the cooling of the kiln (which is often desirable for pottery).
  4. However, total energy saved is minimal in low-fire applications. This is because 3" brick takes more energy to heat itself up.
  5. We definitely recommend 3" brick for high fire applications (over cone 1 - 2000F).
  6. See brickstudy.pdf for details. 

Front-Loading Kilns have thicker insulation

  1. All L&L Easy-Load and Hercules kilns have 3" of firebrick backed up with 2" of mineral wool.
  2. We use 4-1/2" K25 firebrick on the arches of the Easy-Load kilns because of the extra strength.

Special Applications

  1. We use K25 firebrick for our JH series kilns.
  2. This brick will not shrink as much at extended soaks at high temperature.
  3. The K25 brick is denser which actually aides int he cooling of the JH kilns which give those kilns more controlability.
  4. K25 brick is stronger.

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