Insulating Pizza Oven

[digitben]

Hi - I'm in the middle of a very slow project to build a pizza oven! So far I've built to base, insulated the base and laid firebricks for the cooking stone. Also started building the dome using bricks (couldn't afford to use fire bricks for the whole thing!). Now, looking at the insulation I'm a bit worried. I have a load of insulating fire bricks (very lightweight, easy to cut) which I was going to use on the outside (then render), but see most people use an insulating matting.

Is the matting more accomodating/flexible for expansion so does it reduce cracking!? If I use the insulating bricks, should I simply rest them on the outside (allowing for movement) and then render between and over to fix, and not between the inner dome and outer? The render I'm using is a mix of sand/fire clay/ lime and cement.

Any help would be really appreciated, I tend to go around in circles with these things!

Best regards
Ben

[Jon in Albany]

I dont know the difference in cost but the thermal blanket insulation I used was about 300 hundred US dollars. I think the reason the blankets became popular is how quickly they can be applied. They are also very good at holding in heat.

I personally don't have any experience with insulating bricks. I have seen builds where they are used under the deck. Maybe there is a build on the Forno Bravo forum with an insulated bricks on the dome. Sorry I cant help you with this.

One thing I did notice is the size of your vent. It is kind of hard to tell dimensions from the photo. It looks like you have the space of 1 brick for the smoke to go up the chimney. I used a 8 inch diameter pipe, so about 50 square inches and still get some smoke out the front sometimes. You might want to consider a bigger opening for smoke to leave up the chimney.

[digitben]

Hi Jon - Thanks ever so much for getting back.
I can certainly see the speed advantage of the matt, it was my original plan to use before getting the bricks! Interesting you mentioned the vent, I was planning on using a 130mm (5inches) flue. Oddly I have seen smaller and so hoped it would be ok. Good point though, will maybe grind it out a bit!

Have to say your oven looks stunning

[Jon in Albany]

Thanks for the kind words. One of these days I might actually finish building the enclosure!