My not so well-planned pompeii build

[Saltycave]

Mine has been really dry so far, even with all the driving wind, rain/snow we had it was really dry, Ill try to get some photos during or after to show. But also note that I did add, some additives to my stucco mix which were suppose to help make it more "resistant" to water, but concrete is never truly waterproof. I used lumber got from a local sawmill to keep the cost way down. just looked it up and here were my cost/material list
-Pine-
6 - 6x6 8ft 144$
8 - 2x6 8ft 51.20$
2 - 4x4 8ft 20.26$
12 - 1x8 8ft 54.26$
$ 269.72 total
granted the red cedar shingles i did the roof in may have cost about the same as the structure but I wanted that look.

Some other numbers that may be helpful on your older questions.
I used bought 210 bricks and had about 8 left over (mine is 36")
I built on top of my floor and I did solder the first corse
I have a bluestone edge or counter around my oven that is pitched outward. Any rain or water that does manage to get there will roll off and not into my base
Figure out what you are using to cut your bricks with, and make a jig. Then practice a few cuts to learn which way the jig moves to adjust. I cut a whole row the wrong way after confusing my bevels and angles degrees from the spread sheet

Awesome, thanks for the detail and cost breakdown. Nice! Now my wheel is turning, however sometimes I think the hamster is dead. lol

[Saltycave]

Here's a couple questions about insulation board.
I can get the insulation board in my area but they only carry 1" thick. The 2 sizes they carry are 24"x36"x1" ($98) or 48"x48"x1" ($210)
1. Is it best to get smaller size to cover almost a 48" area? or a one piece is better? (I'm wondering if these come not perfectly straight)
2. Can I get away with only 2"? I was thinking, if I can create an airspace between the 2, it should give me a better insulation without extra cost.

[UtahBeehiver]

That is quite expensive CaSi. 2" is adequate for most builders. The CaSi can be layered and staggered vs a one piece. You should consider p or Vcrte as an option due to the high CaSi cost.

[Saltycave]

Can millboard be used instead of casi board?

[david s]

Unfortunately it goes to mush if it gets really wet, unlike Calsil which retains its strength when wet. Both will go back to normal once dried.

[Saltycave]

That is quite expensive CaSi. 2" is adequate for most builders. The CaSi can be layered and staggered vs a one piece. You should consider p or Vcrte as an option due to the high CaSi cost.

Actually comes to $160usd for 1"x48"x48"

[Saltycave]

Unfortunately it goes to mush if it gets really wet, unlike Calsil which retains its strength when wet. Both will go back to normal once dried.

There goes my luck, I was driving through a town and a friend told me there was a place that sells high heat insulation boards so I stopped in and foundout they only had millboar, I didn't have time to wait or research and bought the millboard. lol
I know there should be no water (or very little) under the oven...so the water that would mess up this millboard would have to come from the build, correct?
Is it a bust or can I use it anyway and be mindful of water getting on it?

[UtahBeehiver]

There is a main issue with Kaowool 1401 millboard, beyond water saturation (by the way, water in floor insulation is one of the most common problems with these ovens), is the compression strength is really quite low 10-20 psi at 5%. typical compression strength for CaSi is around 75-100 psi at 5% compression. This means there is the potential of the dome and floor settling and shifting. You should really reconsider the use of this product, if not, caveat emptor. It would be advisable to research the products before you do large expenditures.

[Saltycave]

There is a main issue with Kaowool 1401 millboard, beyond water saturation (by the way, water in floor insulation is one of the most common problems with these ovens), is the compression strength is really quite low 10-20 psi at 5%. typical compression strength for CaSi is around 75-100 psi at 5% compression. This means there is the potential of the dome and floor settling and shifting. You should really reconsider the use of this product, if not, caveat emptor. It would be advisable to research the products before you do large expenditures.

No doubt I screwed up but they will take the product back

[Saltycave]

Hey all, been a while but I'm almost ready to get this started again. (42" inside diameter oven)
Just a few things more to get locally (mortar mix, perlite or vermiculite, etc…) , I have the main materials (big items) ready, (fire bricks, foamglas, ceramic blanket)
Oven will be going on my 4" slab.
Here's a few questions...
1. I'm going to start with 2" foamglas, on top of that a 2" either perlite or vermiculite, and about .5" fire mortar layer to set oven fire bricks floor. Should I go with perlite or vermiculite? And do I need 2" or could I use less?
2. I was thinking of starting with the first dome row with half soldier blocks. I could cut the bricks in half at a 20 degree angle. Would it be of any help starting with an angle?

[UtahBeehiver]

1. FYI, you do no mortar the floor bricks down, they need to free float for expansion and contraction. Same with joint between floor and first half soldier. You can do a 50/50 sand clay slurry if you need to level bricks but not a setting mortar. 2" 5 to 1 por v crete equal to about 1" CaSi

2. Up to you on the bevel,use you IT to see what the angle is and decide it you want to bevel the top of the soldier, my guess the angle on a 1/2 soldier will be slight Half soldier is better than a full soldier, less outward pressure from the dome.

[Saltycave]

Ok, good call on the mortar floor. I should of known that. I did notice some motaring their floor down.

ill go with the 2" v-crete. Thinking it should be plenty to reduce heat to the foamglas row.
I may just opt out of 1/2 soldier

[UtahBeehiver]

Why do you want to opt out of 1/2 soldier? A full soldier may require some buttressing. A half header is an option as well.

[Saltycave]

Not to worry, i change my mind lots lol

[Saltycave]

Any good examples of what to do for moisture evaporation to escape from dome insulation area?