amateur question about insulation construction

[rodallen]

Hi Folks,

Well I ...

• went on a clay oven building course (thanks Terry!)
• attempted to build my own out of clay but it was too small and the fire would not stay lit
• built a bigger one out of clay but it collapsed (poor recycled mud and not enough clay I suspect)
• took the plunge and built a sort of short brick barrel shaped oven
• attempted to plaster over it with a combination of layers of clay/sand and finally cement
• cooked pizzas in it last year - really happy with it

However I am no builder and I was impatient. I suspect I did not let it dry out properly and should not have tried to use a clay layer under the cement as it developed some massive cracks and the whole outer shell has come off. I have cleaned it off now and its back to just the simple single layer brick barrel oven. I have read some posts and seen some youtube clips with tips on insulation so I have bought some chicken wire and ceramic blanket from Vitcas in Bristol and am just wondering exactly 'how' to fit it all. Does anyone have any tips for me please? I will attach some photos to this post later so you can see exactly what I did and what I am dealing with now.

Initial questions are

Q1) - Should I attempt to use large surface areas of the ceramic blanket and just cut bits to help wrap it around the oven or should I cut it into relatively small squares and glue the patches on ensuring minimal gaps

Q2) - Similar sort of question but for a different material - should I attempt to use large surface areas of chicken wire and just cut bits to help it wrap around the oven or should I cut it all into relatively small squares and then twist/link them together? (never used chicken wire so I literally have no clue what to expect when I unravel it - it seems to be rolled up in a tube)

I gather that once you have a layer of ceramic blanket covered with chicken wire that it will sort of stay put and it should be 'safe' to just cement over it (simple sand and cement blend mixed with water - then paint over it?)

I always find it hard to post these sort of questions as I never know if I will be shot down in flames although most people on here seem really nice and helpful so I am optimistic

(and yes I promise I will post some small photos Terry - I know you like to see photos of peoples attempts )

Cheers

Rod

[cobblerdave]

G'day
It's a very fair question, all of us have been there.
CF blanket is good in a way because it's pretty stiff and will stay where you push it without flopping down.
You wrap it around the oven then use a knife to cut down to the dome. Fold the pieces down and cut the bits that overlap of and press it down. The of cuts you can use in the small spots.
The wire much the same but it's there to give the render something to " bite " too. Again wind it around the oven structure cut out the mouth and cut down to you meet the dome. Fold over and twist the wire ends together. It will gather strength pretty fast. Get a bit a bit too baggy, grab a bit with the nose off your plyers and twist sideways over a bit and and it will come good. Don't be too fussy.
Render mix is 3 sand 1 Portland cement 1 hydrated lime. Put it over the dome wait till it's just going hard and use your trowel to mark the surface so the next coat sticks... Hence this is the scratch coat.
The next coat a bit more lime to make it a bit softer and resist cracking between the layers. Again don't be to fussy you'll build up the shape in three layers I'm sure.
IF you just can't help it and play with the mortar with your bare hands, use neat vinegar on them, takes away the sting. Will not heal them or make them less rough but it's great to get rid of the itch.
Regards dave

[charliediggle]

Hello, I'm just doing my research and having read around a bit here am feeling despondent.
I'd thought I might be able to do this: I'm practicle but not great at fine detail. I've never laid bricks.... My garden is one floor down from my front door which is the only access. Do I give up now?!
Rodallen's post above heartened me as he has clearly had a go and then had another!
This has to work first time or my husband will ban me from trying again.
Any suggestions for the most straight forward foolproof way of building an oven to cook pizza and bread in very gratefully received.
I am in Bristol so Victas is nearby.

[darrellme]

Hi Charlie. If you search for the Forna Bravo plans, they have detailed plans of how to build a brick pompeii pizza oven, including size, materials required, tools required, and various images of different ovens. This is what I've based my oven on. I then used Google Sketch to design the layout and size. Its a free tool that you can easily create a 3d image of what you're planning on building, and also lets you design it to scale and retrieve the measurements from it. Its pretty straight forward to use. Once you've done that you can contact Liam at kiln linings for fire bricks insulation, etc, and he is pretty good at advising on how many you need etc. There is an account with Jewsons where the members of this forum get discounts on various materials, wood, bricks, etc, etc. I've never laid bricks before previously but because you're building it yourself, if you don't like something then simply take it down and start again :-). Don't be disheartened as it is so worth it when it starts to come together

D

[cobblerdave]

May 14, 2015 13:36:04 GMT charliediggle said:

Hello, I'm just doing my research and having read around a bit here am feeling despondent.
I'd thought I might be able to do this: I'm practicle but not great at fine detail. I've never laid bricks.... My garden is one floor down from my front door which is the only access. Do I give up now?!
Rodallen's post above heartened me as he has clearly had a go and then had another!
This has to work first time or my husband will ban me from trying again.
Any suggestions for the most straight forward foolproof way of building an oven to cook pizza and bread in very gratefully received.
I am in Bristol so Victas is nearby.

G'day charlie
All of us are first time builders! Hit the search for the term" first time " it will keep you reading for months.
As for not being a "details person" forget that, it's not a disadvantage. You have to start with a whole view of this thing to start with anyway.....
Just do it
Regards dave

[allnjms]

Hi Charlie
I am also new to the forum but I am a builder. However when it comes to pizza ovens I know nothing.
This forum has been a great source of help for me.... Now to only find cheap firebricks.