Yes, using solar powered attic fans. BUT I'd much prefer a powered setup. The solar setup was really expensive and I highly doubt the CFM claims. I can't recommend the fans I purchased from an online retailer - one was broken on arrival, retailer refused to honor warranty. But they others do work well on sunny days and the kiln has performed very well.
Originally Posted by Alex Snyder
Thought of something that applies to the door header. When I built houses, figured out a way to make a header that is stronger than normal. Used a pair of 2x10's at bottom of header, and top of header a pair of 2x4's. Laid a sheet of plywood on the first half of the header, used glue and flat 2x4's on each side vertical and nailed through both the bottom header, top header, and flat 2x from both sides. Makes your entire upper wall into a header. Butt your ply together in the middle, the glue and nails will keep it from spreading, and keep your header flat. Be sure to prop up your header straight, as if it is sagging as you build it, it will sag the same way stood up.