Barrel vault?

[ceeyahd1]

I am in the process of building a barrel style oven, my base is already built and I already purchased the correct firebricks, 3" insulation board for the hearth and sides and 2" blanket for the dome. Originally the plan was to build a 36X42 oven with a 12X20 rectangle door opening offset about 4-6" and 16" dome height, since I have a little space to play with I would like to go 40" wide X 36" deep, what problems will this create if any? what other dimensions would I need to change to make this work?

Is it a problem to build sidewalls with the bricks on their side? there will be 3" ins. and blocks supporting the walls so I don't think there will be any support issues.

Thanks in advance for your help.

[Tscarborough]

Re: Barrel vault?

Blanket provides zero support, so no, you should not use the base bricks vertically, you will need to buttress the arch in some fashion. The size is no issue, other than being a lot of mass to heat soak. What is the primary use of your oven going to be?

[ceeyahd1]

Re: Barrel vault?

Thanks for the response.

Blanket will be used to insulate dome, side walls will have 3" ins block ins. And cinder block for the support. So what I would to know is having 16" dome height with 1 12x20 door opening ok? I got the dome height from a friend that has a 36 X 42 barrel oven and I was not sure if this would change if I went to 40 X 42.

Primary use will b for pizza and occasional bread and what ever else, before I start getting the lectures on what is the best oven for pizza I have to say that the pizza that comes out of my friends oven is amazing, perfect on top and bottom and no question for me barrel is the way to go even if I was only using it for pizza.

[Tscarborough]

Re: Barrel vault?

The shape doesn't matter, what matters is how much mass you need. For a once or twice a month or even weekly backyard oven, you neither want nor need a lot of mass, nor do you need a large floor space. If you are making bread twice a week you would need the mass, but otherwise no.

If it is a true barrel vault, that is half of a circle, then you do not normally need any extra bracing, though a fibered parge coat is still a good idea. The flatter you make the arch, the more buttressing you need.

Given your dimensions, 36" wide by 20" tall, you have a flattened vault and will need buttressing of some sort. A blanket to perform has be loose and fluffed, hence it can not act as a load transfer device between the dome and the 4"CMU enclosure.


Just as important is the opening height in relation to the ceiling height, it needs to be in the range of 60-65%, even on a barrel vault.

[Tscarborough]

Re: Barrel vault?

Mine uses a particular type of construction, but the point remains: It needs to be buttressed. Note that during the construction of the chimney, my dome supported 25-30 brick, a mortar tub, and my 215 pounds with no issues.

Note that the second course brick is notched for the actual arched brick. That is all the buttressing I calculated I needed.

[ceeyahd1]

Re: Barrel vault?

It will be half corcle. My dimensions are going to be 40 wide X 42 deep, is 16" dome height OK?

Thanks for your help.

[Tscarborough]

Re: Barrel vault?

40" wide as a true barrel would be 20" high. The flatter the better, but you have to devise a way to buttress it. And that is a huge oven, with the attendant mass that goes with it. The one shown above is 22" wide by 36" deep, and is more than adequate for everything from bread, to turkeys to brisket plus 2 or 3 sides or pizza.

As small as the mass of my oven is, and as well insulated as it is (6-18" of loose fill perlite), I still normally fire it for 3 or 4 hours for a good heat soak. 40x42 is going to need time and a lot of wood to get to operating temperatures.

[dakzaag]

Re: Barrel vault?

Ceeya,
TS knows a thing or ten about the barrel oven, just check out his build and more importantly his pics and video's of food coming out of that fire breathing apparatus.

[ceeyahd1]

Re: Barrel vault?

My neighbor has a 36 X 42 vault and it is decent size I don't think it's that big. I keep reading posts that vault or barrel ovens take hours and a ton of wood to heat up, my neighbors oven takes about 45 minutes to heat up and as I mentioned earlier pizza comes out perfect on top and bottom.

Will check out ts build for sure when I get home but I still have the question regarding dome height, what should it b for 42 X 40? 20"

[Tscarborough]

Re: Barrel vault?

I can cook pizza in 45 minutes, but the oven is not heat soaked enough to be used later. It will also not be able to produce 45-90 second Neapolitan pizzas, if that is one of your goals.

The answer to your question is that the lower the better, with the issue being the lower you take it, the more buttressing you need on the side walls. If you do not plan on providing a means to handle excess thrust on the vault, you will need to keep it close to 20" and parge it. At 20", the door should be around 12-13" maximum in height, width not as important. What is the design of your throat area?

My home build:

Outdoor Kitchen

[ceeyahd1]

Re: Barrel vault?

TS thanks for all your help. I am actually copying my neighbors oven WJW, if u remember a couple of years ago he was building his oven and posted some questions on this forum, I am very happy with the quality of food that comes out of his vault oven and I would prefer a rectangle vs round oven. I do not have a design for the throat area, I was planning on copying WHO'S oven design but go 4" inches wider on the interior. Please let me know what you suggest as I have everything ready to go but will not start build until I have all the information needed.

[Tscarborough]

Re: Barrel vault?

I found his thread, I remember his oven. Build it exactly like him and you are good to go. Note he uses board between the oven wall and surrounding CMU, not blanket.

edit-incorrect, he has both.

[ceeyahd1]

Re: Barrel vault?

TS I plan on building the same oven as WJW, I just wanted to double check on the dome height since I want to go 4" wider.

[okn]

Re: Barrel vault?

I built mine with the bricks on the side and used the insblock to buttress the sides. I have plenty of mass to bake bread. I've cooked two batches with the entire oven full and had beautiful results. If you want to do more than two batches then maybe you'll need more mass. Take a look at my simple oven - http://www.fornobravo.com/forum/f43/...els-19037.html

I'm local to you. If you need any knowledge, help, sour dough starter, etc. send me a PM or talk with Bill, he may still have my number.

Kevin

[ceeyahd1]

Re: Barrel vault?

Kevin





Bill is my neighbor and I am building the same type oven as bill's. This weekend I finally got my walls up and plan on finishing the dome during the week, final size is 40X42,12x20 door opening with 19" dome height.