Other oven builders recommend using Insulating Castable on the oven exterior as added insulation. Thoughts?

While several brands approve of this method, we do not. We recommend using stucco as the outer layer / shell.

Many a time I’ve looked out the back window and have seen a few kids climbing on one of our ovens. Kids climb - it’s a fact of life. If our oven was built with Insulating Castable as the outer layer / shell, the outer oven would be more susceptible to damage as Insulating Castable is a light weight material and not designed for oven protection.

Stucco on the other hand has thousands upon thousands of fiberglass fibers in the mix which act as tiny rebar in the dry stucco finish. Once the stucco is fully cured, it is nearly impossible to break! And even with the slight chance that the stucco does crack or break, the fiberglass fibers will hold the stucco together with minimal damage.

So Climb Away Kids… Climb Away. And make me a pizza while you’re out there!