Today I have done a few odd jobs to finish off the kiln.
The bottom door has been modified (thank to Joe Finch for his timely advice) by cutting out the lower half of the insulation to allow for air to enter the lower half of the firebox (below the perforated shelves. This will help burn the embers that fall onto the shelf from the fire bars. The iron work has been painted with anti-rust paint. The right side damper bricks have been numbered for quoting in the firing log.
The whole kiln has been encased with at least 5 cm of ceramic blanket kept in place by iron mesh sandwiching aluminium foil. The roof has at least 10 cm of ceramic blanket and foil overlayed with 3-4 cm of an insulating mix of fire clay (15 parts), vermiculite (70 parts), powered scrap insulating brick (10 parts) and a little sodium silicate to help bind it all together. Should keep out the cold!
The final touches to the chimney. Ironwork up to the shelter roof and again to the top few feet of ordinary house bricks. This has been taken above the level of the bricks so that an extra couple of layers can be added if needed. A stainless steel cowl has been added and fixed with wire but can easily be removed if necessary.