Our Brick Ovens from Authentic Pizza Ovens will crack far less than typical brick ovens. However, all brick ovens may develop cracks - these will not affect cooking in any way (and your pizzas will still be marvelous!)
Often, if your oven gets too hot too fast (before proper curing), you may see cracking. These are only cosmetic and won't affect your oven's performance.
However, for cosmetic reasons, we include the ULTRAFIRE patch kit in case you want to fill in any cracks.
The ULTRAFIRE should be put on your oven when the oven is hot using a paint brush. When working around the brick face, it is easier to use a smaller brush with stiff, short bristles to keep the ULTRAFIRE substance off the brick face.