"Pompeii" corner WFBO project in Loei, Thailand

[TxGR]

I am building an outdoor kitchen at my house in Loei, Thailand. The centerpiece will be a wood-fired brick oven (WFBO) using the Forno Bravo Pompeii oven plans. I am also relying upon the forum at https://www.coolthaihouse.com/ for specific Thai constructions related matters.

The previous owners had a structure between the house and carport. This was torn down, but the slab was left. Some of it is uneven, so I will have a new reinforced slab poured over it. The yellow line is where the oven will go.


The basic layout is per this imperfect drawing (I work in IT, but I'm a bit of a luddite, so it is drawn by hand)


I was curious how big the WFBO will look, so I went ahead and laid out the "soldier" course of bricks to get an idea.


The materials were ordered from BST in Bangkok and shipped to Thailand. I contact them on line based on a recommendation by Vinz here on FornoBravo.
BST Refractory
02-420-1231
Line: @bsthai
Sales Manager, Chanipa Wisitnorapatt
Mobile: +66-95-326-5451

About 600kg of materials were shipped to Loei from Bangkok for THB8500 (they used a dedicated truck) and they even helped to offload them.

They had everything required. The firebrick is 31.88% alumina. They also sell refractory mortar, ceramic fiber blanket, and ceramic fiber board (too insulate hearth from oven).


I found this wet tile/brick saw at Hardware House Bangna. They shipped it to Loei (60kg) for THB900. Ideally I could have tried to have it ride up with the bricks, but without a vehicle in Bangkok and on short suspense, the required choreography was beyond me. The folks at Hardware House Bangna were very friendly and helpful. They also were the only ones in Thailand actually carrying wet tile saws.

[UtahBeehiver]

FYI, the FB oven plans are a good base but a little dated, there have been many design and construction improvements by the Forum members since the original publication of the edoc by FB. Right off the bat, is there a particular reason for using full soldiers on the first course of the oven rather the a half soldier or even a half header. Full height soldiers may see an outward pressure from the dome above possibly require that you buttress the outside of the soldier course. Half height soldiers or half headers you are more self supporting. See attache brick diagram. PS you are doing it right by redoing the oven foundation. The ovens are really heavy and need a properly build foundation/slab.

[UtahBeehiver]

arch force.JPG

[UtahBeehiver]

One more thing, the wet saw is a bridge saw so you will have to develop a jig of some sort to do compound cuts required for the oven.

[TxGR]

Thanks for the feedback. The bricks were laid out to give me an idea of scale mostly. I have not definitively decided on whether to do full height or half height for the first course. In the version of the plans I read, the authors recommended half-height, but mentioned some 36" ovens use full height. They did not explain why, so thanks for that. I've seen some comments about the need to buttress the first course. Some have written it is necessary, other's didn't do it and had no issue. Of course, there could be other factors in those cases.

In all the videos I've watched and all the threads I've read, I don't think I've seen any two done identically. Even in the plans, there are many variations. I was leaning toward full-height in order to give me just a little more vertical space in the opening, but you've definitely given me something to think about.

Labor here is very inexpensive (future post). Accordingly, power tools are not as widely used, or at least advanced power tools are not used, and so the selection in stores is very limited. I went to many different places, contacted others, and sought leads trying to find one. I only ever found a wet saws in one place and the choices were very limited. Still, I think this saw is decent and the price matched to the same saw in Europe (still more than in US). The entire bridge folds over to do angles and bevels. The saw can also be raised and lowered for plunge cuts. For anything more complicated, I might resort to my grinder or the true Thai method: a hacksaw and chisel.

[TxGR]

I am contracting out the slab, stand, and hearth. The FB plans call for a stand made of cinder block. In our first meeting, the contractor said he could do cinder blocks, but I'd have to source and purchase them myself. He suggested he could do it more economically pouring the walls/supports, all reinforced. While I see some form of cinder block used extensively in Thailand, most of them are only half wide (I guess 40x20x10 cm). I went ahead and asked him to quote pouring the walls/supports. The quote was very reasonable, so I approved. They started framing that afternoon.

As I read Thais don't use much wood in making forms for concrete pours, I was curious to see what they were going to do. Whereas in the Texas, we use pine for everything, most of it is treated as disposable, although some is reused for other forms or improvised items. In Thailand, they used metal, something like c channel, probably the metric equivalent of the 2x4 dimension. They tack weld everything together and have no issue separating and tack welding it back to adjust the height -- they were putting it up and taking it down like it was velcro. The welds weren't even messy.


They drilled into the existing slab to put rebar in around the new slab/cap, and also into the sections of wall that will support the hearth.


There is a saying, "this is Thailand," to explain why some things are done differently. Using soft wood (like a pine equivalent) in Thailand would be expensive and in many cases a huge mistake due to the moisture and insects. In reading over at coolthaihouse.com, a forum about foreigners building their own homes or making large improvements, most often an owner is better off letting Thais do things the way they know how. That is what I decided to do with the foundation, base, and hearth. Almost all the homes and office buildings here are built out of cement and cement products, and so they are both knowledgeable and pretty good using these methods.

In other areas, "this is Thailand" might explain why something is done a certain way, but is not a defense for it.

This welder was using sunglasses for eye protection.


The worker cutting rebar just looked away.


For leveling, they used a water level. I've used them before, but usually over long distances, like across a yard. I offered to lend them my 3' level, but they prefer to use what they know and to which they are accustomed. I do the same -- which is why my drawing is a physical hand drawing instead of a CAD rendering done on a $500 application where I had to spend three weeks just figuring out how to draw a circle.


At the end of the first partial day, they'd completed the general frame outline and placed some of the rebar for the wall of the hearth base (pic taken next morning).

[TxGR]

Today, a slightly larger crew returned about 8am and worked until noon. They kept working on the rebar, welding some, tying most, and doing a lot of bending.


By lunchtime, they had completed most of the rebar for the hearth.


After lunch, they put down mesh. They originally planned to pour today, but they postponed that until tomorrow.


Tomorrow I am leaving for a few weeks. I expect this portion to be done when I return. Next, I'll start doing my part: putting down FB board, cutting bricks, and laying everything out. I hope to start around December 27th.

[UtahBeehiver]

Lots a ways to skin the cat. The base is bomb proof will all that rebar in it. When you do have the hearth poured, make allowances for weep holes so water can egress out or drill them in after the fact. Wet floor insulation is one of the most common problem for poor oven performance.

[TxGR]

Thanks for the proactive suggestion about weeping holes. They will have to be added later. Is this moisture in materials outside of bricks, or for water, like rain, that settles on the hearth?

i’ve not Yet decided how I will finish the oven. I like the look the Spanish Colonial look of the oven in the YT channel Wood fired Oven Chef, however, that look is not Thai. Also, they don’t have the small, roughly 5”x5” tiles common in the US for countertops. I thought about tiling the hearth around the oven. We shall see.

Thanks again, I appreciate your input.

They finished the slab today, and I’m very pleased. I might be able to make a post later tonight with pics.

[UtahBeehiver]

Initially water in the material and construction but this disappears during the curing process. Rain on the hearth or the front of the oven opening are water sources later. This is why is is suggested that the CaSi board not sit directly on the hearth (it is really water absorbent. Some builders set the CaSi on spaced out ceramic tiles where the tile channels are over the weep holes. I used a non absorbent layer of insulation called FoamGlas for the first layer but this product may be really hard for you to find in Thailand. Also some builders install a v or pcrete layer first then the CaSi.

[TxGR]

I’ll be back in the US for the next two weeks. Reading about foamglas, the marketing emphasizes “lightweight,” but provides no comparison or actual weight. I’m sure there has to be someplace in Houston carrying it, if I can find a supplier willing to sell a small quantity.

Ceramic tiles, usually 40x40 or 60x60cm are very common in Thailand. They use them for floor and wall covering. Almost all flooring is tile.

Going through your build photos now while waiting to board.

[UtahBeehiver]

IMHO, you are better off using local ceramic tiles to raise the CaSi off the hearth. I can send you a cut sheet for FoamGlas if you PM an email address. Distribution International out of Houston use to carry FoamGlas, I got mine from them at a local branch office here in Utah. Not sure it is worth the effort be haul back to Thailand.

[TxGR]

I was considering tiling the hearth around the oven, but I suppose I could tile the hearth first, then build the oven on top. Given the weight on a dry surface, I can’t logically come up with a reason against it, but something about building on top of a hard, slick surface of a tile just seems like an error. That reminds me, I need to tell the contractor to prepare the hearth surface for tile.

thanks

[UtahBeehiver]

Use a coarse surface tile or something else, pavers, etc. The main purpose is to get the CaSi off the hearth surface.

[david s]

I was considering tiling the hearth around the oven, but I suppose I could tile the hearth first, then build the oven on top. Given the weight on a dry surface, I can’t logically come up with a reason against it, but something about building on top of a hard, slick surface of a tile just seems like an error. That reminds me, I need to tell the contractor to prepare the hearth surface for tile.

thanks

Where the base of the dome meets the supporting slab is often an area that develops a crack which can then provide a path for water entry. A cement shell meeting a glossy tile is likely to result in a less than ideal bond. It is also a good idea to slope the supporting slab away from the dome to discourage water pooling at the dome base and possibly running under the dome. This can be achieved with some leveller before glueing any tiles down.