Cristobal Cristo

I live in hot summer Mediterranean climate in a continentalized version - with high summer temperatures and light night freezes in December, January. Due to foothill location the sun is more intense than lower elevations.
Anything that would be left elevated and in full sun would be dried in very short time. It would have to be watered probably 4 times a day or more.
This year I have tried to do sunken beds, by using tractor single plow to go 30 cm deep. I have planted cucurbits and okra and used woodchip mulch around plants mixed with some manure. The watering in the sunken beds was easy and the water was staying around the plants, but... the berms created by the trencher worked as solar lens, accumulating heat and radiating into the plants. As a result I got only 2 watermelons (citron, so not even a regular sweet one) and zero melons, zero cucumbers, 1 zucchini, zero beans and maybe 10 okra pods. Pumpkins got fried the fastest. Out of 40 tomatoes, 5 survived, but as usually they did not produce fruits due to high temperatures and when they produced them in late October it was too late for them to ripe as usually. Pretty ridiculous and pathetic for a large garden.
For the next year I will fill the trenches with compost and will continue flat gardening. I'm also going to set up drip irrigation for the vegetables as watering 3 times per day by hand and in scorching sun takes quite a lot of time and effort.

Ytong/Hebel (aerated concrete), Silka (lime based), expanded clay concrete block and Porotherm bricks all offer tongue and groove systems in Europe. They are mainstream materials available in most cities. They normally are not dry stacked but laid on thin (or normal) mortar bed. They could be dry stacked, because they have very precise dimensions (Porotherm can be purchased with post-firing ground bottom and top). In case of seismic Porotherm the vertical openings could be used for reinforcing the dry stacked wall. Silka is sold with vertical openings for wires and pipes and they could be also used for reinforcing.
ICF forms are dry stacked by design and then filled with concrete. I think they are quite great building method as long as they are natural like Faswall/Nexcem and do not contain synthetics like exterior styrofoam (loved by mice, termites, toxic when burning, nasty when disposed).

Matt,

Traditionally white ovens were not used for baking, but for lower temperature operations. "Baking" traditionally means bread.
In case you use the shelf you have a choice of using 5/8, 3/4" or 1" version. I would recommend 3/4 as they definitely feel more robust. I would recommend to design (or purchase) your heater/oven doors in such a way that you will be able to remove and replace the shelf if needed.
If even the steel white oven with kiln shelf floor will not be satisfactory you will still have an awesome oven of the firebox. Please insulate the firebox floor really well and then the side walls. You will be able to cover the shelf with removable insulation material to improve the firebox oven performance. If this case you could put another thick shelf/slab on the 3/4 kiln shelf and then put some insulation to increase the firebox ceiling thermal capacity for the following baking session.

One 5/8 shelf supported by 4 posts holds around 14 kg of pieces that I fire, so 30 lbs. The span between posts that supports 15 lbs is about 8" wide.

Regarding the white oven, please be aware that it may not work as you wish. Usually white ovens are made from steel or cast iron and are used while burning.

I have built a two chamber oven. I use the bottom chamber (being also the firebox, 200 mm BBR equivalent) for quick baking and when cooler, for slow baking and cooking soups/stews. It gets up to 450 C.
The top chamber is installed on the path of the riser exit and gets heated to 230 C. So already the black oven is twice colder despite the hot exhaust blasting it for 3 hours. It's much more massive than yours, but also more powerful and insulated quite extremely.
In baking, the most important is the floor, but if the walls are cold, nothing will be baked. I remember when I was baking in my improvised oven. The floor was hot - still covered with hot coals, but too cold walls resulted in failure.
If the interior of a brick oven will not get penetrated by hot exhaust it may just get warm and not more. The exhaust gases will freely travel in the bell and not so much energy will be left to heat the oven walls from the outside and even if they got heated, the inside will be too cold. When my temporary oven got heated by direct fire (not expanded and colder exhaust gases) to pizza baking temperature, the outside was just hot to the touch. Imagine to have it in reverse - outside quite hot and inside just hot to the touch but too cold for any baking.
If such an oven was constructed from steel with the slab floor then there would be a chance that you can be happy with it.

I do not want to be negative, just want to share my findings. It would be great if you could try it outside first - dry stacked. I know it would be an effort to dry stack the bell, but it would be worth. If you found that it does not work you could try to fabricate or purchase a metal oven and then see how it performs.
Even if it fails I can see that your firebox will be quite massive with wall bricks laid as stretchers and additional lining. If you insulate under the firebox floor with insulating bricks or at least 4" of perlite clay, insulate the walls and the slab, you will get a wonderful oven.

May Lotito wrote:Do you have tips to speed up the ripening process?

No tips. I have so much sun that I rely on nature in this regard. There will always be unripen fruits on the tree. I you have a large and productive fig with strong root system, that will be able to regrow after hard freeze it will produce a lot and the wasted unripen fruits will bother you less.

Molly,

I can share my experience. Just ask questions.

Matt,

Actually the thinner kiln shelf is exposed to less breaking forces.
The breaking torque at the heated element is expressed by formula:

M = (deltaT * E * W^2) / 12
delatT: temperature difference between two sides of the heated element
E: elasticity coefficient
W: element thickness

So the M is proportional to the power of thickness.
I have a ceramic gas kiln and use 5/8" shelves and so far only one developed a hairline crack just above the propane torch where temperatures reach 1200 C for few hours. I also fire heavy objects so the shelves are under more stress.
Your slab will store more heat. Are you planning to make it a black or white oven?

May,

I recommend that you also try "Hardy Hartford" fig. It's possibly even hardier than "Chicago". It also tastes better. I have 40 various figs and "Hartford" scores at the top for the flavor in my opinion. It is also very hardy for extreme heat. It survives the southwestern corner of my fig plot and also at the top of my frying pan orchard. It is also extremely productive, much more than "Chicago". It was still making new figs in November. The only other fig with such production level is "Florea" - even more cold hardy (grown commercially in Bulgaria and the Balkans)., but with not so great flavor as Hartford. I would recommend that you try both.

This is my old post about the lime plaster. I have improved the text a little bit.

This is the mix that I use for compressed earth block, clay brick and concrete.

HOW TO MAKE LIME PUTTY
Ingredients for 20 l bucket:
-12 kg high calcium hydrated lime (make sure it's calcium lime not dolomitic Ca/Mg)
-10 l (more for additions) water
Tools:
-20 l bucket
-lid (if no lid is available then cover with plastic bag/film, then piece of plywood and secure with stone/brick)
-powerful drill with mixing paddle (I use Bosch hammer drill with SDS+ paddle)

Pour water into the bucket and add most of the lime and keep mixing till smooth. Occasionally you have to scrape the walls to reincorporate drier material into the mix that can not be reached by the paddle.
Keep adding the remaining lime and some more water. if needed The consistency should be very smooth, thicker than thick sour cream but a little thinner than cream cheese.
Smooth and level the top with the trowel, cover with 2 cm of water - all putty has to be covered - otherwise uncovered sections will dry.
It takes around 10 minutes to make one bucket of putty. Let it "age" for at least 2 days, so it will be more uniform.


HOW TO DETERMINE SAND TO PUTTY RATIO
Tools;
-sand
-isopropyl alcohol - at least 70 %, the less water the better so it will be less sticky
-measuring cup with 250 ml mark

Collect 250 ml of the sand you are going to use. It has to be completely dry. If not dry, then bake it in the oven. Fill the measuring cup with sand to 250 ml mark. Put it on a level surface. Start adding alcohol with a measuring spoons till the surface of sand is wet, but NOT more. Record the volume of alcohol added.
The volume of alcohol added to the volume of sand is your putty to sand ratio. For my sand it is 1:2.2.


HOW TO MAKE THE PLASTER MIX
To a wheelbarrow or mixing tray add sand and lime putty in the determined ratio Keep mixing. It will seem way too dry and you will be tempted to add a lot of water, but add only a little bit - a cup or few cups and keep mixing till smooth and uniform. Then you can add more water for desired consistency. At this moment you may add pozzolan (ash, pumice, ground bricks) and fibers. I add rice straw, cut to length no longer than 3 cm - 10% of sand volume used for the plaster.
Please remember to always smooth the top of remaining putty and cover with water and a lid.

One 20 l bucket of putty (12 kg of dry lime) is enough to plaster 5 m2 of wall (plaster thickness 10 mm).
Before plastering clean the wall, brush it, and whitewash with the putty+water mix (creamer consistency). It will create an interface for the plaster layer. It's important - especially when plastering adobe/cob.
When the whitewash solidifies after at least 24 hours, then spray with water and start plastering.
Protect the lime plaster from direct sun/high heat and temperatures lower than 5 C
Keep spraying the plaster with mist of water for a few days. In hot dry climates you may want to spray at least 3-4 times per day for 5 days. I recommend using large sprayer with a hose. The bottle sprayers are too small for larger jobs, have lower pressure and less capacity.

For larger jobs it helps tremendously to buy some used food grade barrel for mixing the putty. It took me 25 minutes to make putty from 70 kg of lime. If I did it in 20 l buckets I would spend over an hour.

I have not tried adding pozzolan yet. I have a pallet of extra fine pumice and I'm going to use it on exterior walls of my house.

Peter van den Berg wrote:I agree about he plaster, there's a possibility they'll skip that eventually.

I think the grey pavers plus cognac mortar combine into some Nordic/Central European aesthetic theme and look great. Also the dark color of the bell helps with faster heat radiating.