Poll: How hot is the outside of your igloo?

[scottz]

Re: Poll: How hot is the outside of your igloo?

Hey Rossco,
I live in Atwell, and we have a brand new Kitchen Warehouse just up the road at the new South Central Cockburn aswell as a new Bunnings and heaps of other shops. I do love that shop (could spend a lot of money in there!!!) and I did pick up a book called 100 Pizzas and Flatbreads from there. But they also have a WFO their store and do demos too. I did a cooking demo with the mob I bought my kit off in Forestfield and was really suprised at what can be done! Really recomended that everyone goes to atleast one show to see what their WFO can really do!!

[nissanneill]

Re: Poll: How hot is the outside of your igloo?

My 40" Pompeii is insulated with a 1" superwool blanket (I think that there is a second layer over the top section also), and then 3" of vermiculite cement and then a 1/2" render.
After a roaring fire, the oven over 500˚C for a couple of hours, the top and any parts of the dome outside is only ambient air temperature, ie. no appreciable increase in temperature.

Neill

[kebwi]

Re: Poll: How hot is the outside of your igloo?

@nissanneill: Wow, 1" blanket + 3" vermicrete on the sides and 2" blanket + 3" vermicrete on the top with no noticeable heat. That's incredible. Nicely done.

[ThisOldGarageNJ]

Re: Poll: How hot is the outside of your igloo?

Hey Keb,
The only place i get heat is around the entrance way bricks.. they will get up to 200 degrees (f) during heat up... I can run the oven for hours and the snow wont melt off the top,,,,

[dpike]

Re: Poll: How hot is the outside of your igloo?

I have 2 inches of kaowool, and approximately an inch of vermicrete on my igloo, all in town if you want to come and look. No noticable heat on the outside of the dome when at full temperature, and the underside of the concrete slab that the dome rests on gets to about 100 degrees F.

[david s]

Re: Poll: How hot is the outside of your igloo?

We've had a deluge of rain up here, rain gauge over flowing daily. I fired my oven for the first time in a few months and the outside was hot to touch (it's normally just a bit warm at the top.) Obviously some moisture has got in and the insulation is not so effective. It's also very very humid here in the tropics, so even though the exterior is weatherproof moisture has got in. It took me 2 hrs to get to temp which is way slower than usual. The wood was also damp which doesn't help.

[tfasz]

Re: Poll: How hot is the outside of your igloo?

Useful information.

I'm still debating between 2" and 3" of insulation - looks like it would be about $100 per 50 sq ft. roll locally for some 8lb Superwool insulation (Superwool - 1 In Thick - 24 In Wide Synthetic Vitreous Fiber - 8 Lbs Per Sq Ft). Sounds like 50 sq ft equals about 1 layer, so $200 for 2" or $300 for 3".

I'm thinking I will probably start with 2 rolls and see how far I get and then maybe add a 3rd if necessary.

[BackyardPermaculture]

Re: Poll: How hot is the outside of your igloo?

tfasz,

My oven is reasonably small and is not an igloo - it's enclosed. But my insulation worked out significantly cheaper than that:

- A 25 sq ft roll of insulation easily covered my dome/arch once, with enough to cover the top twice.
- Insulation is "Tombo" brand rockwool, made in Indonesia. It has an operating temp of 650c (1200F)
- 2" thick roll, so my dome top has 4 inches over it

The whole roll cost me about $50 from an industrial insulation guy - not sure if it's available where you are, but it works really well and was a great price.

[DimTex]

Re: Poll: How hot is the outside of your igloo?

I used the insulation offered by Forno Bravo, bought three boxes and laid down 4 layers with some left over. My oven may get over 900 degrees F but the outside has always remained the same as the ambient air temperature. I can see how much I have left over and if you'll cover shipping I will send it to you for free?

[tfasz]

Re: Poll: How hot is the outside of your igloo?

@DimTex - Thanks for the offer - would certainly be interested. Someone else in the Seattle area mentioned they might also have some Superwool left over. How much do you think you have left? Send me a PM or e-mail me via Gmail at toddfas. Thanks!

[100million]

Re: Poll: How hot is the outside of your igloo?

My oven is 100 F when my oven on the inside is 1000+ and it takes about 1 hour to 1 hour and 15 mins to heat up

This is the BEST PLACE TO BUY all your insulation..... They have scrapes and it is cheap...

http://hightempinc.net/

[ksm]

Re: Poll: How hot is the outside of your igloo?

I have a Toscana from Forno Bravo; the outside only gets up to 100F even after three hours of high firing prior to bread baking (the laser gun maxes out at 974F and the dome is hotter than that for the last two hours) . The underneath gets very warm to the touch as well. I've never bent down to aim the laser at it to get a specific temp, though. This Toscana is built from the older Casa 100, with an extra inch of mortar over the dome and an extra layer of insulation under the hearth. It would have the "FB standard" insulating blanket over the dome.

[tfasz]

Re: Poll: How hot is the outside of your igloo?

Chris - thanks for the tip on HIGHTEMP INC.. I ordered some Superwool insulation from them Monday morning and it was on my doorstep Tuesday afternoon. No tax, and even with shipping was still less than from my local supplier.

[cobblerdave]

Re: Poll: How hot is the outside of your igloo?

I'll throw this in the pot
My wfo has 55mm 21/4in Hebel cemmet block layer under the hearth. Dome insulation is 1200 C ceramic insulation 1in thick all over and extra inch over the top down to 8in from bottom then this is covered with Fiberglass insulation 4in.
Wire and cement render over this. Works... seems to. Gets warm on top but you can comfortably hold you hand on it. Junction of dome and brick chimney does get noticabily warmer. perhaps the heat travels up the brick. the cement slab remains cool with a warm spot in front.im sure this is because the hebel stops and the hearth bricks continue past them.
before I forget the fire bricks are "lighter" 29 per cent silica.

regards dave

[eprante]

Re: Poll: How hot is the outside of your igloo?

I cooked pizza tonight, the inside of the dome was hotter than my HF infrared thermometer could read ( 1000 F) and the outside of the dome was 89 degrees, about 10degrees above ambient temp. I used the ceramic blanket (2 rolls) sold by FB, then stucco over the top of it. I think James has a winner with this insulation, and his price was better than than I could find for comparable products- no this doesn't mean you should raise your price James!
Here is a picture of some San Marzano tomatoes I picked today to make the sauce.

Eric