Greetings from NY

[delay!fox]

Re: Greetings from NY

Thanks...

If anyone can give any information that will clear up the below questions it would be most helpful. I have the same questions posted in other areas and wishing someone can assist.

After I poured my hearth, I noticed that the the Bag of Vermiculite has the following information. I'm upset that I didn't notice prior to pouring.

BRAND:

A-TOPS Vermiculite Masonary Insulation
Water Repelant For Block & Cavity Walls
Need a little help here guys...

1) Did I screw up and use the wrong material?
2) Will the insulating Hearth function as designed?
3) Will this material HOLD or will it crumble?
3) There is no mention of Asbestos but bag does say to wear a mask?
4) Will I need to REMOVE this layer and reapply? ((YIKES))
5) Does anyone have any other solutions should Hearh be a flop?

[Frances]

Re: Greetings from NY

I think the answer here would have to be that we just don't know... I don't think anyone has used the treated vermiculite before.

The question is, how can you test your vermcrete layer to see if you have to do it over or not.


I would suggest you wait for a couple of days and then maybe walk around on it, to see how it holds up. Check how crumbly the top is. It should feel something like cork. Then ... light a fire on it? Hold a blow torch to it? How do you test insulation for oven buildability?

[delay!fox]

Re: Greetings from NY

Ok... it's my turn to give back on this one...

I contacted the Vermiculite Manufacturer (( A-TOPS in PA )) and asked the questions and would like to share the answers with the Forum to keep some other poor sap from having their oven dreams turn into a nightmare. TFYI there is also another manufacturer of Vermiculite called SCHUNDLER in NJ.

1) ASBESTOS: Per A-TOPS and SCHUNDLER products are Asbestos Free

2) TYPE and GRADE: From what I was told by the manufacturer, The Pool Mix is the best mix for the oven project, however the only difference between the Pool Mix and the mix that I purchased ((Vermiculite Masonary Insulation - Water Repelant For Block & Cavity Walls)) is the Grade. Pool Mix is fine and the Block & Cavity mix is coarse. A-TOPS also told me that the name is misleading "..Water Repelant for Block & Cavity..." and that the vermiculite is Untreated. I wouldn't risk it again.

What is VERY IMPORTANT is that the Vermiculite Mix that you purchase is UNTREATED and PURE in form.

Hope this helps everyone.

If I where anyone else reading this string for information, I wouldn't risk purchasing the mix that I bought. Take the time to read the fine print and ask the questions in respect to the application you need. Contact the manufacturer and triple check. The manufacturer told me that my mix would work ... that is to be seen.

Thanks to you all.

[egalecki]

Re: Greetings from NY

Whew, glad your mix didn't have the silicone treatment.

Vermiculite concrete is weird looking stuff, and the texture is strange too. It never, ever gets to looking or feeling like the other concrete, so don't expect it to. At best, it looks sort of like solid oatmeal. You can pick little crumbly bits up and smash them with your fingers. You can worry around the edges like a mouse and break it up. BUT, when you start laying things on the top, it's tough stuff in compression.

I'll try to get a picture of mine for you, but I have to find the camera first. I cleaned and now I can't find anything...

[Frances]

Re: Greetings from NY

Oh hey, good news!

Don't worry a bit then - for some reason I ended up with the coarse grade too, and it works a treat.

[asudavew]

Re: Greetings from NY

2.5" x 4.5" x 9"

Follow the plans, and INSULATE, INSULATE, INSULATE.

I can cook a brisket or a pork butt in my WFO(Wood Fired Oven) the second day after firing. I usually fire the oven on Saturday, and cook pizza. Then Sunday bread or steak, and Monday I throw a brisket or pork butt in.

Good luck,

Dave

[connie kokiousis]

Question regarding insulating concrete-help!

I have a question about the insulating concrete layer. I am hoping to have my pizza oven base at the same height as my counter (36") like the one I saw in Les's photos. However, my calculations are off and it is going to be about 2" too high.

Can I pour the 4" of insulating concrete just under the igloo dome area (40") and not out to the edges of my 60" x 60" square base? These seems to make sense to me, but maybe I am missing something about the heat retention.

If I do this, I will be able to continue the countertop material seamlessly around the igloo.

Thanks!

[delay!fox]

Re: Greetings from NY

Hi Connie,

I'm new myself to this project so will let the experts respond... I do recall however within the instructions for the Pompeii Manual (Pg. 26) where it specifically states the following which may be applicable:

"If you will be building a landing in front of your oven opening. It is not necissary to pour vermiculite concrete all the way to the front of the hearth. Rather you can end the vermiculite directly under the oven chamber and vent area"...

Again Connie... I would defer to the experts just quoting the "Pompeii Bible".

Dave and friends, I have another question for you all... I know that the oven floor is not applied with Mortar, clear on that. I do however have a question that relates to the FIRST string of cut firebricks... are those placed on the oven cooking floor with Mortar or loose?? If not lose with a mixture and if so what? Thanks all.

[Les]

Re: Greetings from NY

I do however have a question that relates to the FIRST string of cut firebricks... are those placed on the oven cooking floor with Mortar or loose??

I placed my floor on the inside of the dome with the first course just sitting on the board.

Connie - I answered your question in the gallery. You only need to be insulated under the dome, not the entire base.

Les...

[connie kokiousis]

Re: Greetings from NY

Thank you Les and everyone who responded. I can't believe how quickly I am getting my questions answered. Thank you all so much.

Here is another question: The two brickyards that I have been to have little to no answers when I ask if they have low to medium duty firebricks. All they know is that the bricks they sell come in yellow $1.90 or red $1.20 and are used to line the inside of fireplaces. They are 9 x 4 x 2 and weigh about 8 lbs.
Are these actually the correct bricks?

Thanks again.
Connie

[egalecki]

Re: Greetings from NY

If they weigh about 8 pounds each at that measurement, they should be fine. Go with the cheaper red ones if you want- or use both, they look pretty that way!

My soldier course sits on my oven floor and is not mortared to it. I used newspaper strips to keep the bricks from sticking to the floor when I stuck them to each other.

[RTflorida]

Re: Greetings from NY

I ran into the same with my local brick yards...buff colored bricks for lining a fireplace, although one of them was familiar with the term "light duty" and assured me that was all that anyone used in a fireplace. It was either buy them a 77 cents each or go back to the refractory store, get all the info I needed and pay $2.50 - $4.50 for the several sizes and angles they stocked. I chose the 77 cent bricks (call me cheap) and I have had no complaints.

RT

[connie kokiousis]

Re: Greetings from NY

Hi RT,
Thanks for your input. I thought about searching out cheaper bricks, but gas is too expensive.
Connie

[egalecki]

Re: Greetings from NY

I found the camera, and I took a pic of the insulation at the front of the oven, under the floor. As you can see, I probably didn't pack it as well as I should have into the form, but it's holding up fine. You can still pick at it, but it's holding up the oven like a champ. It's just weird looking stuff.

[delay!fox]

Re: Greetings from NY

Hello All,

Guys I'm finished with the Hearth and have decided to add "Split" Firebrick directly on the Vermiculite Hearth as an additional Thermal Mass Layer. I am doing this as an alternative to the "Board". I do believe that the Pompeii Plans offer this as on option. Of course I will be placing the FireBrick floor over the "Splits"

Have a few questions:

1. Should I Mortar the Splits to the Vermiculite Hearth or use the fireclay paste? Considering the number of Splits and Joints that I will have, I'm concerned about keeping the Splits Level under the weight of the Dome.

2. Can I place the Dome's first course of Firebrick directly on the Firebrick Split base, much like I would if I used the board?

Looking forward to the Experts oppinion. If Im estimating correctly, im looking at around 80 - 90 Splits.

Will be posting photo shortly, Being slowed down by the BBQ Stand that Im also building next to the WFO.