Cement rendering a pizza oven is essential not only as a cosmetic element, but also for the purpose of protecting the oven from the harsh environmental conditions and covering the insulating material. For effective cement rendering, polypropylene fibers and iron oxide pigments should be used in the cement coats. While polypropylene fibers are for providing the required strength in the coat, iron oxide pigments are for providing the red color on the oven.
The first coat of the cement rendering should be applied over the insulating materials and should be applied for a depth of 3/8” to ½”. The second coat, which is also known as the browncoat is applied to a depth of ¼” to 3/8”. It should be applied at 900 to the way the first coat was applied. The finishing should be ¼” to 3/8” and it should be the fibers and the iron oxide.
Further information: How to build a pizza oven