outer insulation

[gazzagwire]

Hi folks, after a year of fettling, I'm finally at the stage where I need to choose my outer skin. I'm really swayed by the thermalite block option, but I'd be keen to hear people's opinions in that vs vermiculite.

Cheers

G

[phi1]

I used vermiculite in a cement slurry 6:1 ratio.

Once I got the mix right it went on easily and covered any uneven construction.

I have been able to hold it to a reasonable igloo shape ready for a waterproof render (if it ever stops raining.

I used a base of ceramic blanket under the vermiculite and held it in place with chicken wire which helped to support the slurry on the sides.

hope this helps

Phil

[geoffisegwr]

Hi G,

Not sure what you had in mind for your outer form for you oven, but in my case, i had limited space around my vault so opted for the combination of thermal block, loose vermiculite and double blanket layer. There are some photos on the link below.

The thermal blocks are easy to cut (normal saw) and work with - you could probably create many different forms.

With regards to the insulation properties of this approach, I think it should be ok, but i haven't t had a chance to try it out yet.


ukwoodfiredovenforum.proboards.com/thread/2225/side-opening-barrel-vault

cheers

JT

[kstronach]

if your building an igloo your best bets probably 2 to 4 inch ceramic fiber insulation with a layer of vermicrete over the top followed by your final waterproof render coats this is generally the way most folks do it. thermolight blocks sound a pain to use over the dome to me!!

if your building an enclosure just form the enclosure then fill it with loose vermiculite from the top before you roof it!

keith

[alun]

Another vote for vermiculite (vermicrete). I have heard others don't like it but personally I found it easy to work with and actually quite enjoyed putting it on. As phi1 mentioned you can get a nice even finish - covering up any inconsistencies in your dome build.