Re: insulation limitations

Posted by Rado

In Reply to: Re: insulation limitations posted by Bob K

Bob,
Top of a wood oven made of stones can look nice. It will also cut down on cost/work time. Apply the vermiculite insulation in 3 thinner layers, when the oven should be fired for cooking before every subsequent layer is added on. Mixed insulation applied in layers gets better used to movement and will push less on the final stone. The insulation mix with lime mentioned in the CD is very good for this kind of work as it's soft when set. Add very little water when mixing because vermiculite does not absorb water, mix semi dry. Better if the mixed stuff is not tapped on and also without smoothing that way it stays softer when dry.

For insulation in the front. Because there is only 1" or 25mm space, and if loose vermiculite can not be poured into a closed space, use ceramic blanket. I think I would choose cement board or metal to finish the front. Looks like the area is too thin for mortar and with an insulation under. You can try but if not bound to a firm surface on a larger area the mortar could start to peal off. It could still be fixed later if needed. Rado

Oven building details pages for Insulation Matters, cladding layer, oven thermal mass explained or even the different oven shapes and their functions explained.