FB insulating blanket alternatives? Pompeii Oven Construction Discuss FB insulating blanket alternatives? in the Pizza Oven Design and Installation forums; I'm doing a dome too. I need to do more research on this. I'm not close enough to that point ...

[kebwi]

I'm doing a dome too. I need to do more research on this. I'm not close enough to that point to be making big decisions about it yet.

[kebwi]

@kimemerson: How big is your dome? I'm curious how many of the 50'^2 rolls you are going to buy?

I'm only building a 36". Just curious.

[Oh, you have another thread on this topic. Please disregard.]

[KEmerson]

43"/ 2 rolls + about 4" perlite/cement.

[redmen4]

kebwi,

I am building a 36 inch oven and will use 3 rolls of blanket with no other insulation.

JQ

[david s]

Using perlite or vermiculite is way cheaper, but you have to make your insulation thicker to achieve the equivalent insulation value. You also then have the additional problem of drying out the insulation layer (if you are doing an igloo style) because it takes a lot of water to make the mix so you can apply it.

[james]

The cost of blanket insulation in the US has come down in price to where it is very close to the cost of vermiculite. And it is so much easier to use and it is so much more efficient.

FB will be going 100% solid state (board and blanket) insulation in the near future.
James

[kebwi]

Hmmm, just to be specific about it, adhering strictly to the Pompeii directions for a 36" oven, page 59, dome insulation options are...

Either:
1 blanket = $75 + $30 shipping = $100
+ 3 bags verm/perl ($15 apc, obtained locally) = $45
+ small amount of Portland (dome, not enclosure) = negligable
= $145
or:
6 bags verm/perl = $90
+ some Portland (negiglable?!!)
= $90
or:
2 blankets = $150 + $30 = $180

Okay, it's within a factor of two cost, only 1.5 times if you combine the methods. However, it is worth noting that other folks in this thread are considering going beyond the Pompeii directions, such as three blankets, no verm/perl. Once you start lobbing on additional blankets, the difference in cost between the two methods starts growing rapidly.

Just saying...

[redmen4]

I agree on the cost. Unfortunately my space is very limited and will have to go the three blanket route and the extra cost. Also, everyone says do not skimp on the insulation.

JQ

[lwood]

I'm interested in the perlite/cement vs. blanket question as well. I'm going to have a tough time getting the fiber blanket here in the Philippines. How much more perlcrete should I add to replace the fiber blanket? Or are there other alternatives?

[david s]

There is a comparison somewhere on the forum, but I think you need to go 50% thicker for the same insulation value, but remember that the more cement you add to the vermiculite/perlite insulation the more you reduce its insulating capacity.