What do you have for Insulation

[mrchipster]

Re: What do you have for Insulation

What is the max temp the perlcrete can get to before it starts to fail. I called up FOAMGLAS and they told me that 900 deg F is the max temp with was stated above. Around 1100 deg F the board will start to crack and around 1300 deg F the board will slump and fail.

Perlcrete will hold up but is not the best insulator directly against the Firebrick so I would recommend 1" - 2" of ceramic board next to the Firebrick

Foamglas is very brittle and hard to lay firebrick directly on so a layer of 1-2 inches of creamic board would be recommended next to the Floor brick.

That is how the oven I am assisting with right now is being built.

Floor Brick
1" - 2" Ceramic Board
4" Foamglas

Stacked as above

My oven is

Floor Brick
2" ceramic FB Board
2.5" 7/1 Vermicrete

I wish I had more insulation under the floor.....

Chip

[K79]

Re: What do you have for Insulation

What is the max temp the perlcrete can get to before it starts to fail. I called up FOAMGLAS and they told me that 900 deg F is the max temp with was stated above. Around 1100 deg F the board will start to crack and around 1300 deg F the board will slump and fail.

[V-wiz]

Re: What do you have for Insulation

hmmmm. Ok. This is what deejayoh has recommended:

McGills Warehouse Online Department Store,HF102 2IN Ceramic Fiber Boards Density 17.5lb ft3 or 280kg/m3 D1A F10DF

Should I put 4" of this down or is 2" ok?

The price has gone down, it used to be $115 for the boards.

[V-wiz]

Re: What do you have for Insulation

Hard to get your oven floor much over 900, and even then it is not going to stay there unless you are using a bellows or something.

I recommend McGill's Warehouse for CF goods. Same stuff as our hosts at half the cost, and they are a mail order house. V-wiz' source sounds good too if they are willing to pack stuff up for mailing.

If you are looking for advice, I'd recommend going with a tested material shipped to you (e.g. CF board) vs. sourcing something unknown locally.

McGills is good for the blanket, but the insulation board was a bit expensive. Pacific insulation is pretty good, ive been there twice, the guys was really helpful as we walked back into the warehouse and hand picked some of the boards. They are a large company so i don't see why they wont ship?

[UtahBeehiver]

Re: What do you have for Insulation

fat fingers CaSi on top of FoamGlas

[K79]

Re: What do you have for Insulation

K79,

You only need perlcrete under the fire brick hearth/dome, you can fasten the metal studs to your concrete slab. I did use a combination of FoamGlas and CaSi. 2" FoamGlas on concrete slab with 1 1/2" CaSi on top of CaSi. Which ran be about $200. But like Tscar say, you can save your self some money with Vcrete or Perlcrete but the key is to make sure you don't underinsulate under your oven.

What do you mean 1 1/2" CaSi on top of CaSi? Did you mean on top of the FoamGlas?

[UtahBeehiver]

Re: What do you have for Insulation

K79,

You only need perlcrete under the fire brick hearth/dome, you can fasten the metal studs to your concrete slab. I did use a combination of FoamGlas and CaSi. 2" FoamGlas on concrete slab with 1 1/2" CaSi on top of CaSi. Which ran be about $200. But like Tscar say, you can save your self some money with Vcrete or Perlcrete but the key is to make sure you don't underinsulate under your oven.

[K79]

Re: What do you have for Insulation

Why not just use 50 bucks worth of perlcrete?

Oh man talk about getting overwhelmed haha. Is this the method the FB plans talk about? Doing a 3 1/2" slab with a 4" perlcrete layer? Do you put an island of firebrick in that? Also would this material be suitable to fasten the metal studs to for the enclosure?

[Tscarborough]

Re: What do you have for Insulation

Why not just use 50 bucks worth of perlcrete?

[K79]

Re: What do you have for Insulation

hmmmm. Ok. This is what deejayoh has recommended:

McGills Warehouse Online Department Store,HF102 2IN Ceramic Fiber Boards Density 17.5lb ft3 or 280kg/m3 D1A F10DF

Should I put 4" of this down or is 2" ok?

[Tscarborough]

Re: What do you have for Insulation

It is rated for 900 degrees which is hard but not impossible to do on a multiple day firing. Note that that is not the working rating, it is the point at which it begins to fail.

[deejayoh]

Re: What do you have for Insulation

Hard to get your oven floor much over 900, and even then it is not going to stay there unless you are using a bellows or something.

I recommend McGill's Warehouse for CF goods. Same stuff as our hosts at half the cost, and they are a mail order house. V-wiz' source sounds good too if they are willing to pack stuff up for mailing.

If you are looking for advice, I'd recommend going with a tested material shipped to you (e.g. CF board) vs. sourcing something unknown locally.

[K79]

Re: What do you have for Insulation

I have seen it used, but it is right on the edge temperature wise. Should be fine for underneath on a normal use oven.

On the edge temp wise? It's rated for over 1800 degrees. Others are stating that they use 1200 degree board? Am I misreading something? I definitely don't want to use something that's on the edge of failure.

Thanks

[Tscarborough]

Re: What do you have for Insulation

I have seen it used, but it is right on the edge temperature wise. Should be fine for underneath on a normal use oven.

[K79]

Re: What do you have for Insulation

Ok the distributor just called back the price of that board to put 4" down will cost me around $700 haha. He has another product that he recommends that will cost me $168.

FOAMGLAS:

FOAMGLAS? Boards :: Product overview :: Products :: Building :: FOAMGLAS?, ecological cellular glass thermal insulation systems for durable solutions in building, HVAC installations and industry, produced by Pittsburgh Corning.

will this work? Detailed info link at the bottom has all specs.