Re: exterior temperature. Freezing, steam, water.

Posted by Rado on November 29, 2003 at 08:17:05:

In Reply to: exterior temperature posted by Sid Feasey on November 29, 2003 at 04:20:39:

Freezing itself will not hurt refractory bricks. It's the same as with any other masonry. In the winter months. When the dome is cold start the fire smaller at first and the temperature will spread evenly inside of the mass walls. Just for the first half an hour, that's long enough to avoid spot expansion changes.

This doesn't include water danger. As with the house walls prevent oven structure from the exposure to rain and snow. Water expends as it's changes to ice and it could create cracks in the brick work.

The same with the steam. Steam is very powerful. If water was absorbed into the oven's walls, fire would heat it up rather quickly and changing it into the steam that grows in volume and wants to escape out. As it builds up inside it could result in an even bigger cracks developing -- More ideas for wood burning oven building - Building Details Page.

In the volume sense, one part of liquid water equals 1,000 parts of steam. So it expands quite a lot! No wonder, steam was a part in creating the industrial revolution ~200 years ago.