I'm wondering if there are any designs around for an outdoor kitchen that incorporates both a cooktop and oven. My indoor wood stove has the hot plates directly over the fire box then the flue ways around the ovens so I was thinking of something like that but with the cob oven just being part of the flue way. So the cooktop would be a steel plate above the stove that's fairly well sealed and with an exhaust on one side into the cob oven that also has a door with a good seal. This then exhausts sideways and perhaps down through a bench
Separate stoves gives you more control, and also allows you to fire up only what's needed (may use less fuel if you consistently do one operation more than the other).
A single, all-purpose unit that's always used in both capacities could theoretically take less fuel, since you would be reclaiming some waste heat from one process to heat the other.
One thing I've seen on masonry heaters is a cooktop where the firebox is below. After the fire goes out, you can use the firebox itself as an oven. Works great when space-saving is a priority. Drawback is that often a clean firebox is relatively small and well-insulated. To make a bigger oven, with more heat-retaining capacity, means the firebox may take longer to heat up or require more fuel to burn clean.
Here's a small adobe cookstove, very basic, from India. If you swapped out the bricks on one end for a door, and blocked off one or both chimneys with some spare bricks near the end of the cooking fire, it would probably make a decent bake-oven for one or two loaves of bread at a time. http://e-goodstove.blogspot.com/
The Approvecho folks and allies have done a lot of cookstove stuff, but they seem to favor lighter-weight or metal-based stoves. Ecept when building on-site in areas with more clay brick than scrap metal, once in a while.
I've seen a bunch of different variations on a light-weight pizza oven over a rocket firebox: http://somewhatsketchy.com/?p=115, http://greenrocketoven.com/, http://www.koanga.org.nz/low-mass-insulated-barrel-oven/ For pizza they generally work pretty good. For bread or delicate baking that requires more even temperatures, artisan bakers often prefer the heavier-walled traditional wood-fired ovens. These are not efficient at all unless you are running them every day (it takes a lot of heat to warm that mass up from cold, but not a lot to re-heat it from warm to hot). But they produce ridiculously tasty artisan baked goods, and can take the large and lumpy firewood that might not fit in a small rocket firebox. (It could also be used to make hugel beds, so don't feel obliged to build one of these just to dispose of lumpy wood.)
Here's our massive double-chamber cob oven, burns a little cleaner than the varieties without a smoke chamber / chimney:http://www.scubbly.com/item/75812/instantlink/?affid=8105
You can also add a "smoke visor" over a simple dome oven as an afterthought, but unfortunately I can't find Grant Steven's demo just now (the link's broken).
Erica Wisner wrote:Separate stoves gives you more control, and also allows you to fire up only what's needed
I think you are right. When I think about the way we use our wood stove we almost always have the lids down on the hotplates when using the oven. It would be complicated to build that kind of feature into a cob stove/oven I think.
Erica Wisner wrote:Here's our massive double-chamber cob oven, burns a little cleaner than the varieties without a smoke chamber / chimney