Extra Insulation on Pizza Oven Dome Via Vermiculite and Perlite - September 2025

Now that the pizza oven enclosure sidewalls are done, I could move on to sheathing the roof and button'ing-up the whole thing.  Before I could close-up the roof, I wanted to add a little bit more insulation to the top and sides of the dome.  On top of the firebrick, I have 4" of cal-sil blanket insulation - which I hard-coated.  On-top of that 4" of blanket is going 20 cubic feet of vermiculite and perlite.  I bought these big 4 cubic-foot-bags of the stuff.  Asbestos-free, of course.  

They aren't *that* heavy, so I tug'd each one up the ladder, ripped open the bag and began to pour the insulation in the cavity.  It filled the voids down the sides of the oven along the walls and corners and came-up to the top of the oven.  Adding five-or-so inches of insulation to the sides and a couple to the top.  See below for the vermiculite pour-in:

At the top of the dome and below this truss framing, I put in another layer of 2" CalSil insulation boards - the same ones that I have *under* the oven.  

Everything about this oven build has been 'over-engineered' - from the thickness of the slab(s) to the rebar to the insulation *under* the oven floor.  Why not over-engineer the insulation around the top of the dome?

With the enclosure closed-up, the final step is weather-proof'ing the top with some flashing to keep the water out from around the chimney.  

At that point, I'll be able to check-off #2 on my list:  make oven operational.