36'' brick oven in northern Sweden

[johanr]

Thanks Gulf! Good suggestions for the vermicrete layer. My plan was to continue laying the red bricks four more shifts so the bricks are either flush or an inch higher than the vermicrete. Then fill upp with mortar that figure cut 60x30x3 cm grey natural sandstone blocks are set in. The sandstone surface would overshoot the bricks with about 2 inches on either side and be surrounding the dome on all sides. I plan to keep the igloo shape and cover the dome with 2x2 inch natural stone mosaik tiles (called indostone) that are supposed to be safe for outdoors conditions and frost safe. I initially wanted to cover the dome and perhaps the side surfaces in travertine, but was deterred by the dealer as travertine was said not withstanding frost.
One problem I see with the weatherproofing is that the heating/cooling of the brick chimney/flue creates (as of yet) slight tension in the adjectant render and underlying vermicrete. I am considering grinding out 1/8 inch or so with the angle grinder leaving a gap between the vermicrete/render on the dome and the brick chimney/flue and filling that instead with heat resistant and somewhat flexible caulk, perhaps some silicone variant. But on the other hand I also consider doing nothing about it leaving it as it is and thinking the waterproofing will seal the small cracks that has evolved. It seems as all the cracks that were supposed to develop in the region has already formed. I plan to waterproof the dome further by painting it with a plastic primer solution and then set the mosaic tiles. It should be waterproof enough. Otherwise, I'll build an enclosure

[Gulf]

The oven is looking great Johanr. I went back and looked at the rebar that you have in your hearth. That crack that you see should not be a problem.

If you keep the oven covered when not in use and pay special attention to keeping that vermicrete layer dry until spring, you will be just fine. You can later, chip that vermicrete layer back to fit your dome and entry (and then waterproof), if you are planning to finish as an igloo. You can also chip it back far enough to set plates and studs if you are planning on an enclosure.

[johanr]

So, I have finished the work on the oven for the season. We are getting colder weather now with temperatures the past weeks being to cold for brick laying. I managed to put render on the vermicrete covered dome, and I believe this will help waterproofing it for the winter. I put some waterproofing agent in the render to further this. However, I will keep it covered throughout the winter, when not being used. In spring, perhaps may or early june, I will continue building.
The performance of the oven has steadily improved and now it heats up in a few hours making really nice pizza. One problem I have had is that the structural concrete layer has become warm and cracked in the middle right under the dome from side to side, likely because of heating of rebar. It won't affect the stability and I guess that once all or most of the water in the hearth vermicrete layer has dried out the insulating function of this layer will stop the structural concrete from acting like a heat sink. The vermicrete layer used here was as recommended in the manual, 4 inch.
Now I'll continue to follow all other build threads for more inspiration for the coming season.

[moderator]

Johanr, that bread looks delicious! Well done! You have successfully made the whole Forno Bravo team hungry. ;P

Here is a great bread recipe to try: https://www.fornobravo.com/blog/recipe/tuscan-bread/

[johanr]

Thanks I'm really glad to have this oven to use. It's not finished though. I built a temporary wooden (yup) chimney to use while figuring out the oven, what height necessary, and most of all where to buy the chimney. It's going to be a stainless insulated 1 m high, now ordered on ebay and coming this week. The wooden chimney (insulated with aluminium foil) has worked like a charm, until today when it started smoking on the outside and almost went up in flames. Who would think this could happen?
So I look forward to the new chimney and will take a paus until then.

[Gulf]

Johanr,

That is some very delicious looking food. It is great to see all that hard work finally paying off and that you are enjoying the oven .

[johanr]

Later some chevre chaud and apple cake.

[johanr]

The oven had had much use the last weeks, mostly pizza, bread and drying out tomatoes. Today, we're baking wheat bread at 225-250 degrees C and trying to create steam by throwing ice in a hot pan quite happy with the crust.

[moderator]

Wow. These ovens all look terrific! Good work, everyone!

[johanr]

Ok, now it starting to get hot. A fourth of the dome whitened this evening. But the amount of wood (birch) that has been burnt to get this far! I sincerely hope heating the oven up will become easier continously. Have baked some batches of bread and now they are starting to turn out fine, although still the hearth is hotter than the air inside.

[johanr]

Continueing makings fires, on day 6-7 and feel the floor and sides are getting hotter. Cooked a corn cob yesterday (it was nearby). Will perhaps do some serious cooking this weekend although it is not ready for pizza yet.

[johanr]

Have noticed minor hairline cracking on both sides of the vent arch from day 3-4 of curing. It runs along the brick and expands some when the oven gets hotter and contracts when it cools. Could become a problem later in winter i guess with freeze thaw cycles. I'm considering a shell/tile decoration that may improve water resistance.

[johanr]

Thanks! I agree the search function was way better earlier. Especially on the phone.

[deejayoh]

Try this one

http://www.fornobravo.com/community/forum/pizza-oven-design-and-installation/design-styles-chimneys-and-finish/17312-show-us-your-door-thread/page5

Search doesn't seem to work so well any more. You need to use google

[johanr]

No door built yet. Is there any big thread on door construction? I have only found pics of peoples doors in their build threads. I've cut some concrete plywood, insulated with aluminum foil and used that as a temporary door some nights. Tonight, I am burning away somewhere on day 5-6 trying to keep the temps inside top om entry arch coming to 250C. Still, the floor is much cooler but coming up over 100C at least. The fires are quite big now with 2 logs (wrist like or somewhat bigger size) burning together with a pile of ambers. Flames are sometimes licking the dome top, but trying to keep the a bit lower and going tonight for at least 8 hours already. Am I going to fast or does this seem ok?