Please check if my insulating materials are correct?

[joemyself]

Hi everyone,

I'm about to order all of the insulating material for my pizza oven. For the floor, I plan on doing 2" Foamglas and then 2" CalSil. For the dome insulation I will do 3" of ceramic fiber blanket. Can you please double check that I am ordering the correct material? There's so many options and I want to make sure the specs are correct.

Foamglas
Compressive Strength : 60 psi
Density : 7.18 pcf
Flame Spread Index : 0
Flexural Strength : 41 psi
Insulation Thickness : 2 in
Item Name : Foamglas Block
Length : 24 in
Material : Foamglass
Smoke Developed Index : 0
Sub Brand : ONE
Temperature Rating : 121 to 800 deg F
Thermal Conductivity : 0.14 to 0.54 Btu-in/hr-sq-ft-deg F
Water Vapor Sorption : <0.2 %
Width : 18 in

Thermo-12 CaSi Boards
Compressive Strength : >100 psi
Construction : Flat
Density : >14 pcf
Flame Spread Index : 0
Flexural Strength : >50 psi
Insulation Thickness : 2 in
Item Name : Calcium Silicate Block
Length : 36 in
Material : Calcium Silicate
Smoke Developed Index : 0
Special Features : Non-Water Resistant
Sub Brand : Thermo-12 Gold
Temperature Rating : 1200 deg F
Thermal Conductivity : 0.344 to 0.647 Btu-in/hr-sq-ft-deg F
Width : 18 in


Blanket
Color : White
Density : 8 pcf
Insulation Thickness : 1 in
Item Name : Ceramic Fiber Blanket
Length : 25 ft
Material : Ceramic Fiber
Series/Model : Durablanket S
Specific Heat : 0.27 Btu/lb-F
Sub Brand : Fiberfrax
Temperature Rating : 2300 deg F
Tensile Strength : 7 psi
Width : 24 in


For those that ordered through Distribution International, how was your experience? Seems like they only work with contractors/businesses and not your typical DIY guy.. but I could be wrong.

Anyways, thanks in advance for your help!

[UtahBeehiver]

I deleted the direct commercial links (not allowed) but that said, DI is a good source. I purchased CaSi and FoamGlas from DI and the blanket is the right product.

[Gulf]

+1 on Russell's advice. I too got my insulation from DI. Just make sure that you are ordering the solid Thermo-12 Gold board. The boards on the left in the pic are scored to fit large piping and round vessels. Someone mistakenly ordered the scored for their oven. You want the solid board. It also comes in water resistant and non-water resistant. I believe that the water resistant may have just a little less insulating factor. I have no experience with it. Regardless, you will want to keep you oven dry.

[joemyself]

I deleted the direct commercial links (not allowed) but that said, DI is a good source. I purchased CaSi and FoamGlas from DI and the blanket is the right product.

Whoops. Sorry about that - I did not realize that was against community guidelines. I am aware that posting links to promote a product is not allowed, however, that was not my intention at all and was just linking for help.

Anyways, thanks for your help. It sounds like I have the right blanket material and CaSi board picked out. The only thing I still need help with is the foamglas. Since I cannot post links I will copy over the specs. Please let me know if this is correct?

FoamGlas:

Compressive Strength : 60 psi
Density : 7.18 pcf
Flame Spread Index : 0
Flexural Strength : 41 psi
Insulation Thickness : 2 in
Item Name : Foamglas Block
Length : 24 in
Material : Foamglass
Smoke Developed Index : 0
Sub Brand : ONE
Temperature Rating : 121 to 800 deg F
Thermal Conductivity : 0.14 to 0.54 Btu-in/hr-sq-ft-deg F
Water Vapor Sorption : <0.2 %
Width : 18 in

[joemyself]

I've just updated the original post with specs instead of links. Any help would be appreciated!

[Shaners15]

May I ask why you arent just doing 4" Casi board instead of doing 2" casi board and 2" foam glass?

[SableSprings]

May I ask why you arent just doing 4" Casi board instead of doing 2" casi board and 2" foam glass?

It's because he has chosen the non-water resistant CaSi board, so the FoamGlas will provide a water resistant layer (+insulation) between his concrete hearth and the "water loving" version of CaSi board. The combination of CaSi+FoamGlas board materials will provide excellent heat retention and also help keep his oven floor insulation dry. If he chose to use the Thermo-12 Gold board with the water resistant option, he wouldn't gain anything by using the FoamGlas.

[joemyself]

It's because he has chosen the non-water resistant CaSi board, so the FoamGlas will provide a water resistant layer (+insulation) between his concrete hearth and the "water loving" version of CaSi board. The combination of CaSi+FoamGlas board materials will provide excellent heat retention and also help keep his oven floor insulation dry. If he chose to use the Thermo-12 Gold board with the water resistant option, he wouldn't gain anything by using the FoamGlas.

Exactly. Sable, do you have any insight on the Foamglas I am going to order? Does this look like the right stuff?

Compressive Strength : 60 psi
Density : 7.18 pcf
Flame Spread Index : 0
Flexural Strength : 41 psi
Insulation Thickness : 2 in
Item Name : Foamglas Block
Length : 24 in
Material : Foamglass
Smoke Developed Index : 0
Sub Brand : ONE
Temperature Rating : 121 to 800 deg F
Thermal Conductivity : 0.14 to 0.54 Btu-in/hr-sq-ft-deg F
Water Vapor Sorption : <0.2 %
Width : 18 in

Thank you!

[SableSprings]

Sorry for not getting back to you sooner Joe. The compression value for that FoamGlas block is a little low, we normally look for about 70 psi. That said, because the CaSi sheet will be laid on top, the weight will be distributed nicely & these FoamGlas blocks will work just fine. (I suspect you've already ordered & installed it...so relax & enjoy the build.)

[david s]

+1 on Russell's advice. I too got my insulation from DI. Just make sure that you are ordering the solid Thermo-12 Gold board. The boards on the left in the pic are scored to fit large piping and round vessels. Someone mistakenly ordered the scored for their oven. You want the solid board. It also comes in water resistant and non-water resistant. I believe that the water resistant may have just a little less insulating factor. I have no experience with it. Regardless, you will want to keep you oven dry.

Whilst the water resistant board should be the best option (price consideration) the cal sil with the slots should be a better option than the solid variety (again price consideration) because the slots provide an exit path for moisture to escape, if the board is laid with the slots facing down.

[Gulf]

I respectfully disagree.I don't think that the reduced R-value that the dead air spaces yield make it a better choice over solid CalSil.

[david s]

That may be true, but the increased ability to eliminate moisture more efficiently should more than compensate for any reduced insulation value.

[Gulf]

I'm very sorry David. I still can't come around to your way of thinking on this. Yes, wet oven insulation is about the same as no insulation. But, there have been many discussions on improving water elimination that you, I, and many others have been contributed to which have led to construction methods that improve this problem without using a less efficient insulation. We may have to agree to disagree, but I would like for anyone reading this in the future to at least do some research before determining that scored insulation is "better" than solid.

[david s]

Yes, without conducting specific tests on both types, the two of us are just guessing, but as you say "wet oven insulation is about the same as no insulation" , so keeping or helping it to dry is more important than any slight loss of capacity.
Those with oven enclosures or a roof over their oven are less susceptible to this problem of underfloor moisture. Although in my case, living in the tropics means the oven will pick up moisture from a couple of weeks of really high humidity and no waterproofing or roof will keep that out.
I would however like to take the credit of being the inventor of the drain hole design.

[UtahBeehiver]

I'm cool with David S kudos on the weep holes as well as a host of other innovations especially in the cast oven world. We have seen quite a uptick in cast ovens. If only we can get new builders not to follow the p/vrete main dome ovens so common on YouTube.

FYI, The new version of Thermal Gold 12 is now called Thermal Gold 1200 and is water "resistant" but still no water proof so the weep holes, tiles, FoamGlas are still major options for the ovens.