The first step in building the new version of the biomeiler was to determine the perimeter. This version will be 12’ in diameter to provide greater insulation for the composting core of the pile. The 2022 version was 10’ in diameter and had bubble foil insulation around the sides and over the top. It was an improvement over the 2021 version, which was 8’ in diameter and uninsulated, but it still was not enough to maintain the core temperatures through the winter.
I put stakes in critical locations to ensure it is not too close to the coop or the trees. Based on the positions of these stakes, I found the center for the pile and put in the rest of the stakes. The stakes are 5’ u-posts set 1’ into the ground. Previous versions had no stakes because I filled the pile and straightened the sides as I added the piping in horizontal spirals. This version needs stakes because it will be built in concentric cylinders. Also, because it was a pain to keep straightening the sides and returning the shape to a circle as I built the pile.
In the pile location, I leveled the ground and made a berm around the perimeter. Temperature data collected from the last version indicated that heat was being lost to the ground during the coldest part of the winter. To reduce that heat loss, I put a layer of foam board on the bare ground. This was 2” blue foam board and 2” styrofoam board left over from raised-bed planters we used in the past. Over the insulation, I spread sawdust and raked it to make a sloping surface.
Insulation didn’t make any difference in the planters and was left out when they were rebuilt. It was nice to do something useful with the pieces, because they were in an unsightly stack behind the garage. As an aspiring inventor, I appreciate the value of a scrap pile, but I don’t want us to become “those neighbors.”
A layer of plastic sheeting was spread over the sloping surface to form a drain pan. Any excess moisture that condenses in the pile will drain to a collection point outside the perimeter (lower right in the picture). A bucket catches the liquid, which is rich in nutrients. The liquid can be diluted for use with plants or it can be poured back onto the pile in a spot that may be too dry.
Over the drain pan, I spread a layer of larger wood chips. It is good to use larger pieces because there is greater permeability for draining liquids.
That is as far as I got on the pile work. I spent the rest of the day preparing PVC pieces to build the aeration manifold and cutting fence wire to make the perimeter wall of the inner core.
You have a lot of mental energy, as well as physical ability! This is an exciting beginning to a remarkable endeavor.