1.2M Oven w/BBQ & Tandoor

[Irish Chippy]

Okay, I have drawn out the plan for the base. Have settled on a 1.2 metre inner diameter oven.
Hope to start in a week or two.
I will be using clay bricks for outer and inner domes
My budget is $500

[Irish Chippy]

Am starting the concrete patio of the house, so putting in rebar for base walls. These are all scrap rebar left over from house. Will order the perlite now as vermiculite is harder to get. The cost is $25 for 10KG, but the shipping is an additional $21.50. Grr. That is $46.50 gone out of my $500 budget already. Not looking good.

[Irish Chippy]

I need 111 hollow blocks. I only have 55 or so. Will have to buy 60 more @ $19.00 plus 4 bags of Portland @ $18.00. I bought 300 normal local bricks at 20 cents each so that is another $60
This 'thing' is big. Like almost 4 metres towards the sea, and 4.5 metres wide

[Irish Chippy]

It is over 20 years since Iaid hollow blocks. Not pretty and back breaking. The hand made hollow blocks are different sizes. They are filled with concrete. There is rebar running horizontally on top of the second row. It is 16mm because that is all I have left. The vertical bars are 12mm & 10mm. The weather is very hot.

[Irish Chippy]

600mm cylinder for tandoor ope in counter slab.
1600mm dia x 100mm recess form for half of 200mm slab. The perlite-a-crete will go in that recess after concrete is dry. The plywood is from sign used for my daughter's 3rd birthday

[Irish Chippy]

We will finish the formwork in the morning and pour the concrete soon after
Ciara (pronounced: KEERA) is 3 years old

[Irish Chippy]

• Perlite .................... $25.00
• Shipping ................ $21.50
• 60 hollow blocks ... $19.00
• 4 bags Portland .... $18.00
• 300 bricks ............. $60.00

Running Total: ................ $143.50

[Irish Chippy]

Formwork is complete. I have cement mixer and helpers. Will put 100mm under dome first. Then I will insert the frame above for the perlite concrete void

[Irish Chippy]

• Perlite .................... $25.00
• Shipping ................ $21.50
• 60 hollow blocks ... $19.00
• 4 bags Portland .... $18.00
• 300 bricks ............. $60.00
• 10 bags portland ... $45.00

Running total : ................. $188.50

Base is complete ....

[Irish Chippy]

All the rough work completed now. Will keep the gazebo over it till complete. The sun can be very strong in these months, and besides we may get a few showers of rain.

[Irish Chippy]

The base is now ready for the 100mm of perlite-a-crete to be poured in the void..
The perlite itself is due to be delivered here this weekend or on Monday.
The white you see in the small right side circle is just formwork. It will be knocked through on Monday. That is where the tandoor vessel will go.
It is very hot again here today @34C.

[Irish Chippy]

Perlite concrete - Perlite-o-crete - Perlicrete.
I am thinking 5:1 mix for the base and maybe 8:1 or 9:1 for the dome.
What are your opinions on this?

[Monilee]

I’m actually just trying to figure this out myself. I’m pouring the first concrete base slab today. 3” concrete. I’m thinking I’ll do another pour over this with a perlite slab(5:1) about 4” thick. Then, I’ll figure out what my firebrick layout will be. Suggestions very much appreciated.

[UtahBeehiver]

Those are the correct ratios, 5-1 for base, 8-10 for insulating the dome.

[david s]

I’m actually just trying to figure this out myself. I’m pouring the first concrete base slab today. 3” concrete. I’m thinking I’ll do another pour over this with a perlite slab(5:1) about 4” thick. Then, I’ll figure out what my firebrick layout will be. Suggestions very much appreciated.

Because there is so much free water left in a vermicrete slab and it is the hardest to eliminate when doing the drying fires, it is a good idea to pause after casting it to allow the sun and wind to dry it as much as possible before proceeding to build over it. More explanation in my attached experiment.

Vermicrete insulating slab copy.doc.zip