Starting my barrel vault

[gugahulk]

Re: Starting my barrel vault

No rebar in perlcrete, 4" is better than 2".

Will adding perlcrete increase my mass? in a ratio of 5 to 1? or it will just work as insulation and strength? Remember I am planning on adding 5 ceramic fiber blankets to the vault. I need to make sure they will work great also keeping everything very insulated. I do have the problem of finding wood so I did not wanted to increase my mass if I didn't have to. Please let me know.

[gugahulk]

Re: Starting my barrel vault

to turn 2 bricks perpendicular to the wall on each side and carry those up to the start of the dome.

I cant not picture that comment in my head. Any possible way you can draw something so i can understand it? I like this idea but cant picture it.

[gugahulk]

Re: Starting my barrel vault

Mine is not a barrel oven, I make small precast ovens. Can't really show you, breach of FB rules. You could make a mould and cast the flying buttresses and place about three on each side. If concerned about conductivity and heat loss you could make the brew more insulating where it contacts the inner brick walls. It would look seriously cool.

like some triangles casted like this? 3 of them?

[Tscarborough]

Re: Starting my barrel vault

My ends are keyed, that is, notched to fit half way in and provide a fire seal because that joint is going to open, period. Mine goes from tight when cold to 3/4"+ at full blast.

The simplest way to buttress yours, and it needs it, is to turn 2 bricks perpendicular to the wall on each side and carry those up to the start of the dome. No rebar in perlcrete, 4" is better than 2".

[david s]

Re: Starting my barrel vault

I see, but how would I possibly ad this to the design on the side of the walls? I can not think of any way to ad these to the walls. Any idea on how to do them? I like the idea but just have not idea how to implement it. I would love to see your build, do you have a thread on it?

Mine is not a barrel oven, I make small precast ovens. Can't really show you, breach of FB rules. You could make a mould and cast the flying buttresses and place about three on each side. If concerned about conductivity and heat loss you could make the brew more insulating where it contacts the inner brick walls. It would look seriously cool.

[david s]

Re: Starting my barrel vault

I think Heatstop is overkill, Portland should be fine there as it is not as hot on the outside of the inner bricks. It is normal to use portland against the outside of the inner brick walls.

[gugahulk]

Re: Starting my barrel vault

This is what I meant about the flying buttresses.What is a Flying Buttress? - Architecture for Kids

I see, but how would I possibly ad this to the design on the side of the walls? I can not think of any way to ad these to the walls. Any idea on how to do them? I like the idea but just have not idea how to implement it. I would love to see your build, do you have a thread on it?

[david s]

Re: Starting my barrel vault

This is what I meant about the flying buttresses.What is a Flying Buttress? - Architecture for Kids

[gugahulk]

Re: Starting my barrel vault

OK i see, 5:1 should work fine, you can add some sand in the mix to increase its strength, but remember that the more cement or sand it contains the stronger it will be, but the less insulating it becomes. I'd skip the rebar and use some AR glass fibres.

I would not use Portland cement. I was thinking of using heat stop 50 which is a refractory mortar. What do you think about that? 5 to 1 ratio.

[david s]

Re: Starting my barrel vault

yes, he did do it with insublock but he made a housing for his oven. I will not because of weight issue on my base I will finish the oven with stocco. Isulation block are extremly expensive. They are $99 for only 12 blocks. To me that is crazy. I am thinking if needed I will use perlcrete with a ratio of 5 to 1 and about 2 inches thick. What do you think of this solution? Should I put rebar inside of the perlcrete? or the 2 inches is plenty?

OK i see, 5:1 should work fine, you can add some sand in the mix to increase its strength, but remember that the more cement or sand it contains the stronger it will be, but the less insulating it becomes. I'd skip the rebar and use some AR glass fibres.

[gugahulk]

Re: Starting my barrel vault

That link to WJW's post didn't seem to work. Try this, it clearly shows how he buttressed the side walls with insublock. Like I said you could also do this with insulating brick, vermicrete, or perlcrete. Blanket will compress, but a thin layer will provide support and allow for some expansion.

http://www.fornobravo.com/forum/imag...n/post_old.gif

yes, he did do it with insublock but he made a housing for his oven. I will not because of weight issue on my base I will finish the oven with stocco. Isulation block are extremly expensive. They are $99 for only 12 blocks. To me that is crazy. I am thinking if needed I will use perlcrete with a ratio of 5 to 1 and about 2 inches thick. What do you think of this solution? Should I put rebar inside of the perlcrete? or the 2 inches is plenty?

[david s]

Re: Starting my barrel vault

That link to WJW's post didn't seem to work. It is post no. 58 on "barrel vault in So. Cal" it clearly shows how he buttressed the side walls with insublock. It provides support between the inner oven walls and the reinforced cinder block outer walls. Like I said you could also do this with insulating brick, vermicrete, or perlcrete. Blanket will compress, but a thin layer will provide support and allow for some expansion. you could even do it just at the top of the side walls creating flying buttressing a la Notre Dame, because the support needed is greatest at the top.

[gugahulk]

Re: Starting my barrel vault

First off, you do not need that much vertical brick. 4-5", i.e. 2 bricks is more than you need. The higher the vertical wall vs the height of the dome, the more buttress you need. If you chamfer the top vertical brick, use full bed refractory mortar and parge the dome you are fine.

Tscarborough and David, thanks for the replies. I have seen and studie WJW build. He does not do any buttressing on this build unless I am missing something. The only think that I see that he does is he puts fiber board on the side of the walls and than there is a cinderblock brick next to it. please let me know if I am missing something.

Tscarborough I saw your build. I love it. However my plans are to go 4 vertical bricks than start the arch. I like the look this way better and I also need the hight for what I plan to cook. The big difference between my build and your and also WJW is that I will be closing the front and end wall of my vault inside the vault instead of outside like you did. This will give me extra support for the vault roof. Now my question is, do you think I will still need buttressing even though I am doing that? I was thinking if you guys think I do need it. I was going to mix heat 50 refractory mortar to perlite in a mix of 5 to 1 ratio and ad about 2 inches to the side walls before insulating the vault with 5 ceramic blankets. I would like your input on this an your opinions are always appreciated. if you have any different ideas that will not increase the mass of my side walls I can take that in consideration.

[Tscarborough]

Re: Starting my barrel vault

First off, you do not need that much vertical brick. 4-5", i.e. 2 bricks is more than you need. The higher the vertical wall vs the height of the dome, the more buttress you need. If you chamfer the top vertical brick, use full bed refractory mortar and parge the dome you are fine.

[david s]

Re: Starting my barrel vault

Yes, I think you do need some buttressing on the side walls. Another alternative would be some 5:1 vermicrete in say three places on each side.
Have a look at WJW's

http://www.fornobravo.com/forum/imag...n/post_old.gif (this post shows his buttressing solution).

barrel vault build, he's done a wonderful job.