Heat radiation from external wall of Dome??

[Bert]

Hi Folks

Firstly great web site and forum!

I am in the initial stages of planning a dome oven.

I have sourced good refractory bricks and mortar.

At the moment I am setting out possible locations for the oven. I want to place the oven as close to my boundary as possible, but local council restricts the distance to 450mm from the boundary. The neighbouring property is an additional 900mm from the boundary which equates to 1350mm or 1.35 metres from the back of the oven to the neighbours wall (rendered brick).

I am wondering is this sufficient? I don?t want to burn next door down! I will of course be utilising appropriate materials, insulating bricks below the oven, refractory bricks for the interior, insulation blankets and am currently looking at then covering the oven in sandstone.

That would be my second question, does the internal oven have the ability to support and additional layer of bricks or stone work?

Thanks for your time!

Bert

[Neil2]

Re: Heat radiation from external wall of Dome??

A properly insulated oven does not heat up on the outside once cured. Mine will get warmer from the sun on one side than from heat form the oven.

If you plan on loading the dome, make sure the bottom course (soldier course) is belted to resist spreading.

This can be achieved by using vemicrete for insulation and then a 2 inch or so band of reinforced concrete 6 to 8 inches high around this. The reinforcing for this band could be reinforcing wire rather than rebar. The wire should completely circle the oven. You may have to "dive" it under (or over) where the door is to be.

[GianniFocaccia]

Re: Heat radiation from external wall of Dome??

You will certainly not burn your neighbor's house down but you may, upon oven startup, send some smoke his way. You may want to consider the direction the wind blows across your yard.
Another item of note is that sandstome is extremely porous, and will soak up rain and any other moisture you can expose it to. I'm not sure its a real popular oven enclosure material. Maybe you could seal it?

You don't want to clad your finished oven with any material in direct contact with your dome. Adequate insulation is a must regardless if you render it igloo-style with stucco or bricks, or do the concreteboard and stone/bricks/tile etc.
John

[Les]

Re: Heat radiation from external wall of Dome??

That would be my second question, does the internal oven have the ability to support and additional layer of bricks or stone work?

Bert

Yes - if properly constructed, the dome will support and incredible amount of weight.

[tmarsala]

Re: Heat radiation from external wall of Dome??

Having done the outside render with red common brick I can say that yes, the dome will support the render. Of course, you may want to add a "scratch coat" of waterproof mortar on the outside of your insulation layer (highly recommended) and then render on that. It gives that added support as well.

I believe that several elephant can stand on this dome and it would hold, although I don't want to try it in case I have to build another one! Once is enough!

Tom

[Bert]

Re: Heat radiation from external wall of Dome??

Thanks Tom, Les, John and Neil! All fantastic suggestions that i'll include in the design of the oven. Cheers Alex

[tmarsala]

Re: Heat radiation from external wall of Dome??

Bert-

You're welcome! As a side note, my Finished render is less than a meter away from the neighbor's fence. If you are using the FB ceramic blanket as insulation you will have absolutely zero effective heat loss through your insulating barrier. I was worried about the same thing when I was building.

You will feel the warmth of steam escaping once you are finished and you begin to cure-but don't worry:after several good firings you will notice the outside of your oven being cooler and the oven getting up to temp much more quickly.

Also, I did not use sandstone as my render, but I used it as the deck area around the finished oven. It does absorb water easily and after that last week-long storm I had without covering the dome the sandstone took in quite a bit of water. You might want to consider using something else as render. But, if you do use it, buy a good water sealer and keep that baby sealed annually!

A lot to keep track of for sure! But it is quite a fun project and don't worry too much about the little things-it holds together much better than we think!

Keep in touch-let us know of your progress.

Sincerely,

Tom
42" Pompeii dome

[Bert]

Re: Heat radiation from external wall of Dome??

Thanks Tmarsala!

Yes, I think I may need to re think the sandstone option...maybe go for a composite material i.e. concrete blocks that?s look like sandstone. Alternatively, maybe render and seal the dome then use the sandstone so there is a impenetrable layer between the two. This may also be problematic as the sandstone will absorb quite a bit of moisture which will add considerably to the weight. The sealers I have generally used in the past change the colour of the surface which you are applying.

Bert

[tmarsala]

Re: Heat radiation from external wall of Dome??

Bert-

Yes, they do change the color, but not for too long. I am trying to figure out how to attach one of my pictures, but they are all too large for this site. I'll keep trying.

Tom

[tmarsala]

Re: Heat radiation from external wall of Dome??

Bert-

goto the photo gallery and look on the "finished ovens" category. You'll see mine there. It will give you an idea of the sandstone I used.

Tom

[tmarsala]

Re: Heat radiation from external wall of Dome??

Even better-let me see if I can attach it to this post-sorry, I'm a newbie on blogs.

Tom

[tmarsala]

Re: Heat radiation from external wall of Dome??

Trying again.

Tom

[Bert]

Re: Heat radiation from external wall of Dome??

Cheers!

See the attached link. Its a free picture resizer. This will allow you to easily reduce the size of your pictures.

Image resizing, do it with PIXresizer

Bert

[Bert]

Re: Heat radiation from external wall of Dome??

Awesome Oven! Especially like your brick work at the front!

Bert

[tmarsala]

Re: Heat radiation from external wall of Dome??

Bert-

Thank you! I reattached it on this post. Did you get it? Let me know if you would like more pictures as a guide. It really helped me to see what other people were doing as I built.

Tom