Dogshark58 Build

[dogshark58]

Thanks for that. I was considering using 6" square quarry tiles with a gap between them. My weep holes would be in the gaps between the tiles.

[Giovanni Rossi]

Hello dogshark58, I've seen the pros on the Forum cite this build for pictures of tile between the hearth and the insulation board: https://community.fornobravo.com/for...andpoint-idaho

[fox]

From my personal experience, 2” of ceramic board will still allow the base to be a heat sink, 3” works better but will still allow the concrete to warm up after a couple of hours but is fine generally speaking.
4” of ceramic board (or calsi board) is what I normally use.
Vermiculite will work but is time consuming to make and painfully slow to dry out but it does work ... 4” would be a bare minimum.
On the last oven I built, I tried something different, I use 3” of ceramic board and laid two pieces of 50mm galvanised steel mesh under the board on top of each other so I had in effect a 20mm air gap.
Of course it is impossible to know what is going on underneath but I think it is working well..

[dogshark58]

I was interested in SableSprings's comment about placing a waterproof barrier on top of concrete then adding insulation board. I have a 6" reinforced concrete hearth and I'm about to start cutting bricks. I intent placing 50mm approx 2" of CaSi board on top of the concrete with weep holes. I intend laying the oven floor on the brick edge for additional insulation ie 4.5" will be the brick height.

Given that this build is in Ireland I am concerned about having sufficient insulation.

Questions
1. Is this sufficient insulation?
2. Should I have 2" of cement/vermiculite and place the insulation board on top of that?
3. Does anyone have photos of the tile layer suggested to go between the concrete and insulation as a water barrier. I have some unused quarry stone tiles that were originally intended to cover an external step would they be suitable?

Thanks in anticipation of much needed advice!

[dogshark58]

An update on insulation for those in Ireland. Like eirebuild, I couldn't find Ceramic Fibre board and at times when I thought I had located something useful I was unable to get information on compressive strength.

I have opted to purchase CaSi board from Potterypro, works out at about £27 delivered per 610x500x50mm sheet. Just wondering do I need some vcrete between concrete hearth and CaSi board for extra insulation.

As for firebrick, I sourced this from Ray Graham in Newtownards. The brick they stock comes from Dineen in Athy.

[dogshark58]

I was interested in SableSprings's comment about placing a waterproof barrier on top of concrete then adding insulation board. I have a 6" reinforced concrete hearth and I'm about to start cutting bricks. I intent placing 50mm approx 2" of CaSi board on top of the concrete with weep holes. I intend laying the oven floor on the brick edge for additional insulation ie 4.5" will be the brick height.

Given that this build is in Ireland I am concerned about having sufficient insulation.

Questions
1. Is this sufficient insulation?
2. Should I have 2" of cement/vermiculite and place the insulation board on top of that?
3. Does anyone have photos of the tile layer suggested to go between the concrete and insulation as a water barrier. I have some unused quarry stone tiles that were originally intended to cover an external step would they be suitable?

Thanks in anticipation of much needed advice!

[eirebuild]

Just to give an update for any Irish Builders.
I struggles to find Calcium Silicate board aprt from in the UK.
But in the end I went with Ceramic Fibreboard from Vitcas. These guys worked out to be the best value for me.

[dogshark58]

I have been unable to get adequate confirmation of the compressive strength of locally available Ceramic Fibre board. Therefore I am resigned to using a Cement / Vermiculite mix as the base. I have noted the advice on mixing cement / vermiculite.

I have found vermiculite available from a local building supplier which is described as ...

Exfoliated vermiculite is inert, non combustible, light, clean and has a high insulation value. Used in a variety of different applications due to its many properties it can be used for loft insulation, packaging, chimney lining and high temperature insulation.

I assume this is suitable.

[eirebuild]

Hi DogShark,
Just about to buy some Insulation baord for my own build based in Wicklow.

Who have you decided to go with in the end?

Thanks UtahBeehiver your help is much appreciated.

A bit more success on local suppliers of ceraboard, however waiting to see the spec. Maximum thickness I can get will be 20mm sheets so thinking of about 80mm thickness. I note your suggestion of layering the sheets on different axis to stagger the joins.

I'll post the supplier details once I know it is of suitable quality.

Thanks again for your excellent advice

[RandyJ]

You Can do any size you want. It doesn't have to be just 36 or 42. I did mine at 40" and liked it a lot. Look at your space and see what fits best.

Randy

[JRPizza]

Split the difference like many of us have and build an 39 incher!

[dogshark58]

I have the space to build either dimensions. I would be interested in the pros / cons of those who have completed ovens as to what they would recommend. I see some comments about 42" being only worth heating if cooking for large numbers.

I expect on most occasions I will be cooking no more than 10 pizzas. I may attempt to cook bread at a later time.

[dogshark58]

Thanks UtahBeehiver your help is much appreciated.

A bit more success on local suppliers of ceraboard, however waiting to see the spec. Maximum thickness I can get will be 20mm sheets so thinking of about 80mm thickness. I note your suggestion of layering the sheets on different axis to stagger the joins.

I'll post the supplier details once I know it is of suitable quality.

Thanks again for your excellent advice

[UtahBeehiver]

50 mm (2" for us Yanks) is min recommended floor insulation thickness. You can accomplish with one layer or two, just stagger seams. Min compressive strength should be around 75 PSI or 517 kpa at 5% compression.

[dogshark58]

Thanks for that I'll check it out.

I have found a company in Co Wicklow that sells Ceramic Fibre Board. I just want to check the compressive strength.

IROCO LTD.
Block 3, Newtown Business Park
Newtown Mt Kennedy, Co Wicklow, Ireland

Location: 53.0852N, 6.1058W.

Phone: +353 1 281 0960
Text: +353 87 225 1677
Fax: +353 1 281 0964

Open Mon-Thu, 8-1 & 2-5.
CLOSED Fri, Sat, Sun and holidays.

They have Ceramic Fibre board in sheets 1.2m x 1.0m, the thickness available is 10mm, 13mm and 20mm. I want to have a 100mm (4") thickness and would prefer 50mm thick sheets.