The insulation layer is simply clay mixed with sawdust and built up on the dome. I emptied a bucket of clay into my mixing tub and covered it in water and left it to soak in for a day or two. I then got my trusty mortar mixer to mix the “slip” to a consistency of runny yoghurt! Then I added a bucket or two of rapecore (the chopped straw from rapeseed), which we use as chicken bedding. Most people use sawdust! Build a nice 7cm layer, leave to dry and then do another couple of firings!
Next Step – The last layer