My UK build is out of the ground!

[stonecutter]

Re: My UK build is out of the ground!

The door is 63% of the overall height, but I know where the problem/issue is, and now hoping the oven will still be fine.
The issue is that I have begun my dome shape of the first ring of vertical half bricks, not the oven floor. So in essence my dome is half a brick taller then it is wide.

Dimensions are, 40" width, 24" high.
Opening is 14 3/4 high, 22" wide.
All measurements taken of firebrick floor.

I do realise now that that seems quite large compared to most on here, but it is still 63%, its that my dome is raised on the first course I guess.

Any thoughts?

Cheers

Allan

It is what it is, and yes it will work either way. The goal is the best efficiency possible, and a very large opening isn't as efficient as a smaller opening would be at containing heat. At this point, there isn't anything to do but continue, and it's no big deal anyway.

[Bookemdanno]

Re: My UK build is out of the ground!

Allan, if you found that your oven was losing heat at ridiculous levels. With your skills, you could obtain some more firebrick tiles from Kilnlinings (they do many sizes) and set a new floor to your oven, over the one thats there now. You know the internal diameter, so lay out on a suitable flat surface, scribe the tiles and lay them on a homebrew mortar again.
I have that method in my head for my oven, if the quarry and storage heater brick hearth ever breaks up. But i'd dig the old stuff out.

Very nice work sir!

[stonecutter]

Re: My UK build is out of the ground!

Allan, if you found that your oven was losing heat at ridiculous levels. With your skills, you could obtain some more firebrick tiles from Kilnlinings (they do many sizes) and set a new floor to your oven, over the one thats there now. You know the internal diameter, so lay out on a suitable flat surface, scribe the tiles and lay them on a homebrew mortar again.

Retro fitting a layer of brick over an existing deck has a few draw backs.
First and foremost, since doing that adds a lot of mass to the floor, oven performance will be affected. Also, your transition areas, like the vent area and hearth, are in plane with the oven floor, so raising your oven floor creates a reveal along the bottom.

Something to keep in mind.

[cobblerdave]

Re: My UK build is out of the ground!

It is what it is, and yes it will work either way. The goal is the best efficiency possible, and a very large opening isn't as efficient as a smaller opening would be at containing heat. At this point, there isn't anything to do but continue, and it's no big deal anyway.

Gudday
That's the point really, "it's not a big deal anyway."
All , and I make the point again , All our ovens are that little bit different.
Not that you can notice really, because our ovens are the only ones we will ever really know well. I have friends with ovens , and yes I have opened my big mouth and said" we'll I would to it this way", but really I'm on foreign ground. The tunnel oven cooks multiple pizza because it owner can make it do that, he know his oven better. He would be fairly confused with the firing time with my own for baking.
I have a fair sized entrance, one of the reasons I went the angle iron path. I just experimenting with a "tuscan grill"recon your oven would suit it too.
Anyway on would and upward worry about that keystone
Regards dave

[vincentvega_uk]

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

[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.

[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

[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

[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!

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

[stonecutter]

Re: My UK build is out of the ground!

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

[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?

[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!

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!

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

Allan