How Thick Should the Fire Bricks be in a Commercial Oven?

[Raffy]

Hi James and all woodfired enthusiasts,

I know all there is to build a residential oven, thanks, of course, to all the open source plans and instructions here in the forums. My question is: How thick should i cut the bricks of a commercial oven? I've read alot about thermal mass and since commercial ovens are running almost 24/7, I think the thermal mass of these should be increased so it can retain heat longer to save on wood/fuel. Am I wrong in assuming this?

If my assumption is correct, should I increase thermal mass by increasing the dome thickness thru thicker cuts of brick? Or should I add more fire mortar? And, just as important, how much thicker should the dome be in a commercial oven? 5 in. of thermal layer? 6 in.?

would appreciate the input. Thanks

Raffy

[dmun]

Re: How Thick Should the Fire Bricks be in a Commercial Oven?

James may jump in here, he says that Italian commercial ovens aren't much thicker than the four inches we use in the pompeii.

[Raffy]

Re: How Thick Should the Fire Bricks be in a Commercial Oven?

So when we refer to commercial ovens its just the size difference and all other specifications are the same?

[Raffy]

Re: How Thick Should the Fire Bricks be in a Commercial Oven?

Oh just a passing thought, should I get the low duty fire brick still or switch to the medium for a commercial oven?

[Dutchoven]

Re: How Thick Should the Fire Bricks be in a Commercial Oven?

Oh just a passing thought, should I get the low duty fire brick still or switch to the medium for a commercial oven?

Raffy
The low duty bricks should do just fine. They are continuous use ratings from what I understand that denotes the difference between the two. The only thing that happens in a commercial oven is that it will maintain a more constant temperature for more extended periods of time than one's backyard oven. As for thickness in the walls...if it is primarily a pizza oven then 4 inches should be more than enough...if it is a bread oven for high volumes them more thermal mass would be benficial to allow more loads of bread to be baked.
Best
Dutch

[nissanneill]

Re: How Thick Should the Fire Bricks be in a Commercial Oven?

Alan Scott in his book recommends 12" thick for red bricks and 10" thick for firebricks in a commercially used wood fired bread oven.
This supports Dutch's comments. The thicker walls provide greater thermal mass and longer and better heat control for multiple bread bakes

Neill

[Raffy]

Re: How Thick Should the Fire Bricks be in a Commercial Oven?

Raffy
The low duty bricks should do just fine. They are continuous use ratings from what I understand that denotes the difference between the two. The only thing that happens in a commercial oven is that it will maintain a more constant temperature for more extended periods of time than one's backyard oven. As for thickness in the walls...if it is primarily a pizza oven then 4 inches should be more than enough...if it is a bread oven for high volumes them more thermal mass would be benficial to allow more loads of bread to be baked.
Best
Dutch

Okay I'll stick to low duty fire bricks then. I read something very funny somewhere in the forums... can't remember where. But the person said, "We're baking pizzas here not melting metal." He was responding, if I remember correctly, to someone who was asking the same question about low duty and high duty fire bricks.

My oven will primarily be a pizza oven. Pizza pizza and lotsa pizza hehehe. But I'm thinking of roasting in it too and maybe, as the oven cools down for the night, bake some bread. But this wont happen if I cant find the right suppliers.

I would GREATLY appreciate any leads on insulation suppliers here in the Philippines. I'm partial to those insulation blankets and panels. Please post or email any information to me.

[Raffy]

Re: How Thick Should the Fire Bricks be in a Commercial Oven?

Alan Scott in his book recommends 12" thick for red bricks and 10" thick for firebricks in a commercially used wood fired bread oven.
This supports Dutch's comments. The thicker walls provide greater thermal mass and longer and better heat control for multiple bread bakes

Neill

I'm thinking of a hybrid oven that primarily does pizza but can roast and bake when I need it too. I was thinking of increasing mass a little bit by making it 5 or 6 inches thick so it can retain heat longer and so that I don't have to keep chucking wood in to maintain the required 450 degrees celsius that i need. But based on Dutch's comments I may just stick to 4 inches.

I would like to know people's thoughts on the matter

Raffy

[james]

Re: How Thick Should the Fire Bricks be in a Commercial Oven?

Raffy,

Here's a good resource. This oven is used widely in Italy by restaurants -- it is one of the most popular wood and gas-fired ovens throughout the country. Typically, it is used to bake pizza and a few oven roasting and baking dishes during lunch and dinner, and then for bread in the morning. There are a huge number of them out there -- in fact they are so common, that you often find them in restaurants who don't even advertise that they have a brick oven. They just do.

Unless you are planning on running a commercial bread bakery (bread, bread and only bread; and you do it for a living), it would be really nice if folks would stop looking at the Alan Scott book. It would save a lot of heartache.

Take a look at the dimensions and design of an authentic Italian brick oven. This is the real deal, and there is a lot we can all learn from it.

Commercial Pizza Oven | Modena Design Overview

James

[Frances]

Re: How Thick Should the Fire Bricks be in a Commercial Oven?

Raffy, all the questioning and soul searching will probably only end when you've built your oven and see that it works. That happens to all of us, although I do see that with a commercial venture riding on the result the stakes are a bit higher in your case.

Your analysis sounds about right to me. Look at it this way, if these commercial ovens you see "work" after a fashion despite their design drawbacks, imagine how much better yours will be. I don't know much about commercial ovens, but I can tell you this: the pompeii oven plans work. Follow them and you will have a really cool well built well working oven.

[Frances]

Re: How Thick Should the Fire Bricks be in a Commercial Oven?

Well, I think you're in the right place then. Following the pompeii oven plans isn't actually a risk, its good way to ensure you will have a great oven to work with.

[Raffy]

Re: How Thick Should the Fire Bricks be in a Commercial Oven?

Thanks I will follow the pompeii plans. I'm sure with the knowledge I have now it will be successful. One more hurdle is to find the right suppliers. I lack some materials still. I will update you guys once i break ground.