42" Pompeii - Vent Brick with Thermal Gap

[tmjporter]

First of all, thanks to everyone here for the advice and assistance. This is my second Pompeii and, although far from some of the artistic and inspiring creations posted here, it is far better than my first 36" attempt - which provided us two years of year-round enjoyment summer and winter in Newfoundland, Canada (those are our two seasons :-))

On to the question - I plan on putting a thermal break between the inside arch and the vent / landing by following the suggestions and examples in the forum. My question is can i use regular brick for the landing and vent or do i need to use firebrick and refractory mortar? Also, do I need insulation under the landing if it is physically separated from the oven? Or can i rest it on concrete?

I've found conflicting advice online and wanted your advice. The advantages of using regular mortar and brick are cost and, more importantly, resistance to the elements. The hot part of the oven you see here will be covered with a refractory layer, insulating blanket, v-crete and stucco, then sealed so i'm not worried about that but the chimney will be exposed and i'm not keen on exposing my refractory cement to the elements.

Thanks in advance!
Trevor

[tmjporter]

In the end, i decided on firebricks, just to be safe. I used refractory mortar on the hotspots (bottom of the flue and in the path of the hot air rising up the chimney. I used regular mortar for the front arch. So far, so good!