DIY fireproof mortar question

[amber]

You'd have to look into the specifics, but it's a very traditional technique, so I know there's a way it works. I, however, went with the blanket, so I'm not sure.

[tdibratt]

My first oven was insulated with sand. just typical play sand or the kind you find on the beach. I did put a sheet of aluminum foil over the parged bricks followed by a 2-3" concrete cladding. I then built the walls around the dome and poured sand in. Finally covered the whole thing with another layer of concrete to enclose the sand. Probably a good idea to fire the overn before closing it up to give any humidity in the sand a chance to evaporate.

Worked well for me.

Regards, Tony.