Building in Central Florida, Question about insulation beneath cooking floor

[glowthb]

Re: Building in Central Florida, Question about insulation beneath cooking floor

Thank you all for input.

Dino, Yes. I did use 2" angle iron to bridge the opening opting for the safer easier newbie design. I ground down the 5th course and bricks as needed to accommodate the iron and bring the top of the reveal in at just a hair over the 12.5 inch height after mortaring.

Additionally I will cut off that 5th course at the front back down to only 4 courses bringing the front opening down to 12 inches, 1/2 inch lower than the reveal height. Regarding this, is 1/2 inch enough to trap the smoke forcing it up and out the chimney? I am using 8 inch Duratech system for the chimney.

Thanks again.

[Dino_Pizza]

Re: Building in Central Florida, Question about insulation beneath cooking floor

I agree, 19" dome height is fine. I think it's a great goal. I found it's hard to keep to a lower dome height: the mortar kind of gets out of control and the height creeps up a bit but a 'flat-ish' dome is ideal. It directs the radiant heat down to the oven floor where you want it. And 19" is still plenty tall for casserols or even vertical beer-can chicken.

However, in your last pic, I counted 5 high side arch wall bricks. Most seem to be 3 or 4 hight at most. Are you using an iron "L" bracket/header across the top or still going for an arch? My oven opening is 12.1" in the center and 8.5" at the sides. Just wondering.

Your brick work looks really good, your going to have really nice oven.

take care, Dino

[mklingles]

Re: Building in Central Florida, Question about insulation beneath cooking floor

My dome is 18" high inside. Door is 12" high and 19" wide. Heats well in 1 1/2 hrs. I have lots of thermal couples so I am sure I'm soaking the heat through the floor and dome. You'll be fine.

I can't think of a valid thermodynamic reason for a high dome. A high dome would have more thermal mass then a low dome (assuming both are 4 1/2" high). But you could thicken the walls of a low dome.

A high dome allows a higher door which allows larger items into your oven.

I'm very happy with my dimensions which are vary close to yours.

[glowthb]

Re: Building in Central Florida, Question about insulation beneath cooking floor

Neil,

The full width of the opening may be +/- 23 inches, but the measurement of the inside dimensions at the reveal is 20 inches and the height will be 12.5 in accordance with the FB plans for the 42 inch oven.

I originally planned to build the interior height to the 21 inches but I am reducing it to 19 inches high. I will not get to the dome for another week or so due to schedule. Any thoughts on the 19 inch interior height vs. 21 please let me know if you think its a problem. No particular reason why I am reducing it other than 21 inches looks awefully high and unnecessary. If there is a thermal dynamics reason let me know.

[DrakeRemoray]

Re: Building in Central Florida, Question about insulation beneath cooking floor

Door is probably better a little too wide than too tall...

[Neil2]

Re: Building in Central Florida, Question about insulation beneath cooking floor

You door is 23 inches wide !?

Between that and an inside-the-oven ash drop, I fear you are going to need a wack of wood to get it up to temperature for pizza.

[glowthb]

Re: Building in Central Florida, Question about insulation beneath cooking floor

Man...received my 8 inch Duratech parts today. Much larger than i expected.

[mklingles]

Re: Building in Central Florida, Question about insulation beneath cooking floor

I respect the need to engineer a better mouse trap. I suspect the BBQ enthusiasts will find your "contraption" weirder then the people here.

[glowthb]

Re: Building in Central Florida, Question about insulation beneath cooking floor

Thanks Tom.

Yes it is an ash dump but also hopefully serve as a source of heat for indirect cooking.

I designed my oven to accomodate a second "firebox" in the back of the stand lined with firebrick safe for catching ash or lighting a fire. The opening for the ash dump is through the insulation and stand and into the firebox. Eventually the rear firebox will have a cast iron door with adjustable vent. I will also have an adjustable vent on the oven door. My thought is by controlling the draft I can control temperature for lower temp cooking much like the Big Green Egg.

The ash dump opening is formed with carved fire brick fabricated to lock in place. There is also a specially cut brick that fits in the opening if I want to close it off. I can remove brick through the back oven..a little crude but it works.

I know many folks have posted photos of meat cooked in the oven, but in most pics the meat looks beyond a nice char and outright burnt. So hopefully this design will make it a true low heat smoker as well as pizza oven. Probably not what the pizza oven purists like to see but this is what happens when a guy from the south raised on BBQ spends eight years in Europe enjoying bread and pizza. Is it a BBQ, is it a pizza oven? We will find out.

[ThermoJax]

Re: Building in Central Florida, Question about insulation beneath cooking floor

Hey, really nice work on your build. This will be over all too soon. I tore down quite a few layers on my build as well. You certainly will have sweat equity in your oven. Is that an ash dump at the back of the oven? does it extend thru the insulation and thru the block stand?

Tom

[glowthb]

Re: Building in Central Florida, Question about insulation beneath cooking floor

Knocked out a few bricks and made room for the reveal in the opening. This is actually the second set of vent area walls. The first set I used three individual bricks in each course without any overlapping seems. I was not happy with thinking it might eventually give way. I tore it down and cut the reveal edge out of full brick and made sure the courses were staggered. Seems much better now.

[efleifel]

Re: Building in Central Florida, Question about insulation beneath cooking floor

You can still shift the vent area a little bit aoutwards; about an inch from each side to accomplish the reveal. The other alternative instead of the grinding you can choose to create the reveal in the door instead.
Good luck

Eddie,

My Web site

[glowthb]

Re: Building in Central Florida, Question about insulation beneath cooking floor

Today's progress. I already realized an error....no reveal for the door to seal against. Nothing a grinder and some re-work will not fix.

[glowthb]

Re: Building in Central Florida, Question about insulation beneath cooking floor

Thank you...this is certainly getting to the nerve racking point as far as using brick goes. I have worked a lot with wood and some tile work but the brick is new so I am just trying to work slow and deliberately.

To make the floor I used my template and then shaped the bricks using both a Ryobi Wet Tile/Brick overhead saw and grinder.

Two weeks a go I happened upon the Ryobi tile/brick saw on sale from $199 to $99 at HD. It claimed to cut pavers so I grabbed it and per other customer reviews replaced the factory blade with a Husky. Not the fastest saw or smoothest gliding table, but for what I am doing it has been flawless. Cuts nice as long as you control the speed and it sure beats the rental price, particularly considering the patio is going in after the oven.

[efleifel]

Re: Building in Central Florida, Question about insulation beneath cooking floor

Nice work; how did you cut the rounded bricks?, that floor looks fantastic. I can easily see you are meticulas, and can predict it is going to be a very nice build. looking forward to the rest of your build.
Cheers.

Eddie
My Web site