Today, nature provided me with a cool, crisp fall day, with a clear blue sky and I decided to enjoy the day outdoors. So, shortly after finishing the morning chores, I set myself to the task of extending the inner core of the biomeiler.
The first step of the operation was to clear the insulating layer of wood shavings from the top of the compostable material. Wood shavings in a compressed, saturated layer are less permeable than the compost material in the pile. That being the case, I thought it best to remove it to ensure there will be no hindrance in the transfer of water or vapor between the original inner core and the extension.
After the top of the original inner core was exposed, I secured a length of 28” fence wire around its circumference. The inner core has a radius of 18”. So, the volume of the core extension will be approximately 16.3 cubic feet.
The extension was filled with alternating layers of used chicken litter from the coop and thatch that was raked from the lawn. To monitor temperatures in the extension volume, thermocouples were added along the central axis at elevations of 4 feet and 5 feet above the ground. I made sure the wires were running uphill through the perimeter fence in anticipation of subsidence in the pile.
While cleaning the litter from the coop I was pleased to find it is significantly easier to remove soiled sawdust than soiled wood shavings. A shovelful of either mixture tends to come loose as a block. However, the sawdust blocks break apart easily when dropped onto the floor, leaving only a few small clumps that can easily be broken with a nudge from the shovel. The shavings blocks tend to be larger in volume and more stubbornly resistant to being broken apart.
The only drawbacks I have observed with the use of sawdust are that a greater total volume must be used and more-frequent additions are required in order to keep the coop floor dry. However, since the sawdust is less expensive to purchase and more easily shoveled away than shavings, I have resolved to make exclusive use of sawdust as the bed litter this winter. The drawbacks are minor in comparison to the advatages in cost and labor.
You are retired and have a little unscheduled time to handle the sawdust rather than the shavings ordeal, I would think.
Good luck with that decision. You won’t know the benefit until you have put in that effort.