Adelaide WFO Build

[brickie in oz]

Re: Adelaide WFO Build

Both.

On top of this I will add a base of fire bricks on their side (to increase the thermal mass)

It should be insulation then firebricks.

[vdubber]

Re: Adelaide WFO Build

It should be insulation then firebricks.

Good call. Just reading about this.

Does Perlite / vermiculite + cement in a 5:1 ratio sound right? Been reading a thread over at traditionaloven.com and that's what they seem to suggest.

I managed to get about half of the base done this evening but ran out of bricks. Will stop of at the old red brick co on the way home from work and pick up some more. Also need to find a source for the vermiculite. There's a hydro shop round the corner so I think I'll try there first.

I'm hoping to get the base finished tomorrow and the layer of insulation for the floor poured so that I can let it cure for a day before starting on the rest.

I did manage to find a local suppler for fire clay - A place called The Pug Mill not too far from me. They sell 20kg bags for about $60. Will pick some up tomorrow.

Anyone have an opinion on adding lime to the mortar mix? I wasn't planning on using it, but wanted to make sure there's not some compelling reason for using it.

Anyhows, here's the progress. I did a bit more than this but lost the light to take pictures in. The BBQ goes in the gap between the gas bottle and the return at the end of the brick work. There will be a work are to each side of the BBQ. The wall will eventually go all the way across as the concrete work area will be cast in situ on top of it, it may also get extended upwards, but not 100% on that yet. The gas ring from the BBQ will also get recycled and be inset in the small work area to the right of the BBQ.

Slowly getting there. I can almost taste the pizza

[vdubber]

Re: Adelaide WFO Build

Thanks for the input Doug. Much appreciated. I am working to several different plans, trying to incorporate the best parts of each.

My subfloor is not suspended, it will be hardcore with compacted fill. I can lay down either concrete or insulation mix (or a combination of both) directly on top of this. My plan was to have a 4" subfloor with REOmesh and then lay the hearth bricks on top.

Would I need both concrete and insulation mix ( perlcrete / vermicrete) in this case? I have read that 'perlcrete' is used as a lightweight structural concrete alternative, so obviously no issue with its strength.

There seems to be a few differing opinions regarding the thermal mass of the floor; some say the larger the better, others don't think it makes too much difference. I decided to err on the side of caution and lay the bricks on their side (some even suggest two layers), it seemed like a good compromise. I think I will continue down this path, simply as I have already bought the bricks (plus it's an integral part of the design I have in mind).

Any comments / thoughts obviously very much appreciated.

[nissanneill]

Re: Adelaide WFO Build

vdubber

Also need to find a source for the vermiculite.

Just around the corner from the Old red Brick Co is Thermal Ceramics. They have the vermiculite and are very reasonably priced.

I also have 2 bags of fireclay that I got from Thermal Ceramics for my build if you need some.

Cheers.

Neill

[vdubber]

Re: Adelaide WFO Build

Niel, thinks for the heads up on thermal ceramics, will give them a go. Also, happy to take the clay off of your hands if it's surplus to requirements, PM me with your details and how much you want for it. The offer is much appreciated.

Doug, once again, thanks for the input. I just took the time to read through your build thread; definitely an inspiring read. Seems you are a true craftsman when it comes to building WFO's.

I think I will heed your advice and go for the thicker 'vermicrete', it's no issue to make it thicker, but obviously not something that can be changed very easily after it is built. Do you have a link to the thread about the floor thickness? I would like to read this before committing to laying mine.

The plans I am following are similar to yours, a bit from many sources and lots of great advice like this. I started with Russel Jeavons book, and then found a few online resources such as Forno Bravo. The basic design is still true to Russels book, I'm using fire bricks for the hearth, and whilst I had originally collected red clay bricks for the dome (which all turned out to be too badly weathered to use), I then conceded to use Littlehampton clay pavers. Whilst trying to source the pavers locally I managed to find a builders merchant that had some second hand wire cut clay bricks from a brick oven that had been dismantled, so bought these instead.

The overall aim of the build is to build an outside kitchen area comprising of the WFO a BBQ and a pan / wok burner so that we can entertain and not have to cook in our (small) kitchen. the out-laws have a BBQ under their verandah and use it as an extension of their kitchen, it's very functional, and inspired me to want to create an outdoor kitchen for our house.

The inspiration for the WFO originally came from a trip to Sorento for my mates wedding. Whilst we was there we visited Pompeii and I was overawed with the place. A while later I stumbled across Russels book in a tourist information shop in Mclarenvale and the seed was truly planted.

I've thought about the build for ages, in fact I've had Russels book for about three years now. However, now there is an incentive to get it finished - My daughters first birthday. (Which is a little over 2 weeks away). Pizza is on the menu and we need a WFO to cook them in.

This evening I managed to finish off the kitchen base. Now I just need to fill the oven base with hardcore and then add some fill. Next up is to cast the kitchen work surface in concrete and the oven base in vermicrete. Hopefully I will get this done tomorrow afternoon / evening. Unfortunately I have to take a car for an engineers inspection which will waste most of the day.

Will keep you posted.

Mick.

[cobblerdave]

Re: Adelaide WFO Build

"Anyone have an opinion on adding lime to the mortar mix? I wasn't planning on using it, but wanted to make sure there's not some compelling reason for using it."

Gudday
Sounds like you using the poor mans mix...Portand cement lime firclay and sand? Yes the lime provides the long term, heat proof "glue" in the mix. The portland is there for the initial setting of the mix and as the heat destroys it the lime gets stronger. Use builders lime not quick lime or garden lime. You'll enjoy using this mortar its very different and feels more like mud than mortar to use but it works well.
You hav'nt mention a waterproof membrane yet.... if you havn't use a layer under your base use a bit of builders plastic before your cement slab otherwise your oven will always be damp and hard to use....

Regards Dave

[vdubber]

Re: Adelaide WFO Build

Dave, thanks of the reply.

Yes you are correct, I'm using the 'poor mans mix'

Thanks for the explanation about the lime, I will go get some tomorrow. As far as a membrane is concerned I've added a damp proof course in the brickwork. The slab will be under the level of the pavers and so the membrane will not work as it's basically below ground level.

Made good progress today. With the help of the better half we filled the base with hardcore and I finished a couple of courses that I didn't do last night as it was too dark. I then capped it off with a layer of mesh and concrete leaving enough of a gap for the vermicrete.

Unfortunately Thermal Cermaics was closed today so I ended up getting the vermiculite from the hydro shop around the corner. I bought 3 100ltr bags and ended up using two and half of them.

With the 'vermicrete' laid in, I set about making the formwork for the work surface. On the advice of the father-in-law (a builder) I set a sheet of concrete board as the base. The board is actually left in place. The board does not come to the edge of the 'slab' as the formwork tucks underneath so you cannot see it unless you peek underneath. It's not structural, it simply makes the formwork easier to make.

I then mixed up some concrete with some diggers black to set the work surface in. I decided to colour the surface as I had it spare - eventually it will get tiled, but for the time being I thought why not. Thats pretty much where I left it this evening.

I did take some time to try out the hearth bricks in both orientations, I definitely prefer on end.

Here's some pics...

Hoping to get the dome done tomorrow, but will see how I go.

[cobblerdave]

Re: Adelaide WFO Build

Dave, thanks of the reply.

I did take some time to try out the hearth bricks in both orientations, I definitely prefer on end.

Here's some pics...

Hoping to get the dome done tomorrow, but will see how I go.

Gudday
Consider using the hearth bricks the other way... not on there ends so you dont give the base to much termal mass. You'll find that most ovens take about 2 hours to get to "pizza temp" regardless of there size. Increasing the thermal mass takes more energy to heat yes the oven will take longer to cool down but do you really expend more time and wood to achieve this. Its much easier to increase the insulation to keep the heat in there and save on wood and time to pizza heat.
Your making great progress nice work

Regards Dave

[vdubber]

Re: Adelaide WFO Build

Didn't get the dome up today, mostly as there were no brick saws for hire.

Bit of trivia for anyone who's interested - All hire shops are required to electrically test and tag their equipment prior to each use. For some reason Bunnings do not employ anyone to do this at the weekend. Which means that stuff that's been hired on a Friday or Saturday is Tagged out until Monday, meaning that you can't hire it on Sunday. Funny thing is - I've been caught out by Bunnings the same way before.

I ended up hiring one from Kennings, but then wasted most of the morning trying to figure out how to fit the flue on the front of the oven. I made my base to the dimensions in Russel Jeavons book, 1500mm across, with an 1100mm dome. The difference is pretty much the width of a brick - which doesn't leave a lot of room for a flue.

I did end up deciding to lay the bricks flat, but not until I had laid them all out on end. My decision was partly made by not having enough bricks to finish the flue.

I took one brick out of the centre and substituted it with a red clay brick drilled out to accept the brick / dome gauge. I will swap it back once I've finished.

The flue was proving to be a bit of an issue, try as hard as I might, I could not figure out how to fit in on the base without needing more... erm... base. I eventually admitted defeat and decided to go get the book.

Even though there's not a lot of technical info in the book, there are some helpful line drawings. It was one of these that solved the problem for me. The archway bricks are cut (or at least the first row is shown this way) to match in with the first course. This allows the arch to sit further back towards the centre giving just enough room for the flue to fit. Problem solved.

Having fixed one issue, I then cut the bricks for the arch, trimmed the edge of the hearth and cut some of the bricks for the flue. One thing that I was deciding between was whether to build the outer wall up so that I could insulate the dome using dry vermiculite, or keep the dome shape and then insulate it with 'vermicrete'. For the time being I've decide to do that latter. Whilst I'm sure the rendered dome would probably not perform as well, it definitely has better aesthetics, plus I can always build the outer wall up down the track if I find that the oven does not hold its heat too well.

Building the flue up without the outer wall meant that the arch would probably require some additional support so I decided to make up another arch out of flatbar to help.

Hopefully I will get to actually lay some of the dome tomorrow.

Here's some pics...

[Neil2]

Re: Adelaide WFO Build

"eventually it will get tiled, but for the time being I thought why not."

Have you considered just grinding and polishing it ? Concrete counter tops can look very nice and are all but impervious to heat and to heavy pots being banged down. If you don't like the looks you can always tile it later.

[vdubber]

Re: Adelaide WFO Build

"eventually it will get tiled, but for the time being I thought why not."

Have you considered just grinding and polishing it ? Concrete counter tops can look very nice and are all but impervious to heat and to heavy pots being banged down. If you don't like the looks you can always tile it later.

Yes, but not sure how to do this. Is it easy?

[vdubber]

Re: Adelaide WFO Build

Finally got to lay some bricks today. I managed to get the dome up and some of the flue. I need to return the brick saw tomorrow morning so I will have to cut the remaining bricks with my grinder (I'm sure I will regret this - last time I cut bricks with a grinder I vowed never again - lol).

Need to get another bag or two of vermiculite to render the dome, and still have one counter top to pour, but apart from that I'm thinking pizza is on the menu tomorrow.

Still need to figure out how to fit my 'flue'. I sourced an old red chimney pot, now I just need to work out how it sits on top of the chimney 'stack'.

Here's some snaps of todays work.

[vdubber]

Re: Adelaide WFO Build

As Arthur Brown said...

"Fire!! Bring me Fire!!"

Hehehehe. Lit some small fires this morning whilst cutting the bricks for the arch. But whilst trying to figure out the flue I realised that somehow my arch had managed to rise up a course. Must have got carried away with laying bricks last night trying to use up the mortar.

Oddly enough, even with the higher arch it still draws really well, the main issue I have found is that depending on which way the wind blows I sometimes get a bit of smoke coming out of the front.

Anyhows, just stopped for a coffee and was excited enough to have to post about it .

Off to knock up some muck next.

Next stop lunchtime. I'm getting she who must be obeyed to knock up some pizza dough in the bread machine. Pizza for lunch.

[Gulf]

Re: Adelaide WFO Build

I may have misunderstood the time line of your posts or maybe the humidity in Aulstralia is a factor but, fire, already? wow

[vdubber]

Re: Adelaide WFO Build

I may have misunderstood the time line of your posts or maybe the humidity in Aulstralia is a factor but, fire, already? wow

I let the dome dry out overnight and then lit a small fire this morning, I've kept a small fire going all day which is fun when you're still building the flue

Built it one day - used it the next.

I stoked it up a bit for lunch but it wasn't really hot enough to cook a 90 second pizza

The flue is finished and I'm just cementing in the chimney pot. I've let the dome cool this arvo so that I can render it.

Tonight we will test it as tomorrow the relies are coming over for pizza.

Here's some pics of lunchtimes results...