Bricks are a poor conductor of heat however, in a brick-built pizza oven; they can get hot enough to cause burn accident if the oven is used for long. In addition, then the brick heat up it’s an unnecessary way of losing heat energy which would have alternatively used to cook, the reason why an insulation blanket is used.
The insulation blanket is placed above the bricks and then covered with cement plaster. For effective functioning, the insulating blanket should be placed as to cover the entire main dome of the oven as to touch the foundation in all round the oven in igloo dome oven s and in all the sides for the barrel vent ovens.
Further information: Insulating dome pizza oven and Pizza oven insulation