My UK build is out of the ground!

[Bookemdanno]

Re: My UK build is out of the ground!

You can render directly over the wired blanket, but i may be slightly harder and require an extra layer first, as its not as stable a background as Vermicrete.

[Bookemdanno]

Re: My UK build is out of the ground!

I really doubt that you really need to buttress your arch Allan, unless your going to build a full brick chimney.

[stonecutter]

Re: My UK build is out of the ground!

Yeah true, that's an option. I think 2/3's height up the arch is the rule o thumb if I remember correctly!

Thanks for the Info!

Allan

Most welcome...

Kinda sorta...the span between the buttresses is more important. But for WFO surrounds, you can get away with waaaaaay more than you can with large masonry buildings and walls.

[stonecutter]

Re: My UK build is out of the ground!

Or, build a pointed ( gothic) arch, it wouldn't require buttressing at all.

[vincentvega_uk]

Re: My UK build is out of the ground!

Yeah true, that's an option. I think 2/3's height up the arch is the rule o thumb if I remember correctly!

Thanks for the Info!

Allan

[vincentvega_uk]

Re: My UK build is out of the ground!

No, stucco to the dome and brick vault and entrance arch with twin walled flue. If all go's well!

Allan

[stonecutter]

Re: My UK build is out of the ground!

Rather than building a thick two wythe wall, you can eliminate a lot of mass by incorporating this kind of buttress...



Adds strength to the wall too...nothing is stronger than a corner.

[vincentvega_uk]

Re: My UK build is out of the ground!

I mean adding further brickwork either side of my vault arch, probably 1 brick either side then building this up vertically keeping it plumb and cutting it into the arch until I end up with a flat platform to fix a chimney anchor plate on top of the vault arch.
I know it's not essential to do it this way, I could just create a vault and platform for the anchor plate directly on top of the arch, but I wouldn't mind adding a bit of support.

Allan

[stonecutter]

Re: My UK build is out of the ground!

Brilliant, thanks. Will save me a few ???!

Also what kind of depth coverage with my ceramic fibre blanket do people think I need to do without the vermiculite concrete?
If I have enough fire blanket I intend to chicken wire it then put a base coat of render on before my finished coat.

Cheers

Allan

I'm confused. Are you covering the dome with a brick vault in addition to stucco?

[stonecutter]

Re: My UK build is out of the ground!

When you say buttress, do you mean adding wall thickness or buttresses?

[vincentvega_uk]

Re: My UK build is out of the ground!

Brilliant, thanks. Will save me a few ???!

Also what kind of depth coverage with my ceramic fibre blanket do people think I need to do without the vermiculite concrete?
If I have enough fire blanket I intend to chicken wire it then put a base coat of render on before my finished coat.

Cheers

Allan

[boerwarrior]

Re: My UK build is out of the ground!

yes, buttressing can be decorative brick! Mine is!

Neil

[vincentvega_uk]

Re: My UK build is out of the ground!

I am going to build my vault and decorative outer arch this weekend, and I intend to buttress the vault arches either side to add some stability and prevent any spread.
Can the buttressing be built out of decorative brick? It doesn't have to be firebrick does it?

Thanks

Allan

[vincentvega_uk]

Re: My UK build is out of the ground!

Cheers Stonecutter, I usually over think things!
I was using the 63% rule loosely, the percentage you get is correct, and it falls within the 60-64% bracket.
I guess I just needed a bit of reassurance, having never built or used a wfo before that it will still work and be efficient enough.

Cheers

Allan

[stonecutter]

Re: My UK build is out of the ground!

Firstly, thanks for the advice and opinions on this.

Bookemdanno - That was my first thought exactly, raise the floor to get more of the true dome shape back.
After reading Stonecutters advice, I wonder what the difference in time would be to get the oven floor to the correct temperature if I added a second layer of firebrick? As Stonecutter says, its adding more mass.
Im not concerned about the height difference between floor and vault area if I did this as I can raise that area too.

My other option is to build a smaller arch inside my current arch using cut down fire brick. Reduce the height down to 12" or so. I know it would be difficult to do, but it could be done. This would reduce the opening size, but would also throw the 63% rule. Any thoughts on this?

Thanks Cobblerdave, I do realise every oven is unique, and the difference in my build may not be a big deal, it will still work. After all I know my opening is larger than standard, but it still complies with the 63% rule.

Thanks again all, if I am going to alter something, add another layer to the floor or reduce my arch, now is the time, as when my vault and outer arch is built it will be very difficult to change anything.


Cheers

Allan

I'm not sure if you caught this, but 60% - 64% is an accepted range....oven shape and usage variables effect the final dimension of oven openings.

I am curious about something though. You say your opening is 63%....how do you figure that? You said your ceiling was 24" and your opening height was 14 3/4", I get 61.25%..... Minutiae

If you REALLY feel like you want to raise the floor, don't add a layer of mass to the existing floor. Insulate, then lay the brick on that.

IMO, you won't have a measurable gain by all the extra work, and none of this discussion should cause you concern. For a high dome like yours, what you have is fine, and you shouldn't worry.