Has anyone had experience determining the optimized size of baking stone to gap around edges?
Unless you find a baking stone that fits snuggly within the walls of your oven (unlikely) it's not critical. The important thing is to make sure the entire oven is peheated (walls, bottom, top, stone) before loading the loaf.
The rule of thumb is two inches clearance on all sides (front, back, and sides) for even heating. Ditto for baking sheets. You still have to check for uneven heating and turn your items (or baking sheets) as needed.
Thanks for the rule of thumb.
The conventional wisdom is there should be about 2" clearance on all sides of the stone for optimal/adequate heat/air circulation.
I have a not so large oven(about 18 x 18") but I wanted the flexibility to bake as much and as large a bread as possible. I have only about 1" clearance on each side, but seem to get excellent results.
I imagine the type and condition of the oven and stone may figure into this also. I have an older electric oven with exposed elements but otherwise seems to be in good working order. My stone is a 16 x 16" from nybakers.com.
I had similar concerns when looking into my stone purchase:
Images of my installed stone:
Thanks for supplying the pictures. It never ceases to amaze me how helpful a picture( of something as simple as one inch of space ) can be to bridge the gap between theory and practice.