I am working on building a shack to live in that is of pole barn construction. the walls will have a void of about 10 inches that can be fulled with insulation. I was thinking of useing sawdust since i can get it for free. I am not worryied about the fire hazard this may be as it will only be me in the house. no wife or kids to burn up. I thought about bugs. could i put an insectiside in the sawdust to eliminate a bug problem? what cheap insectisides would work? I have access to about a ton of wood ash as well.would it keep bugs out of the sawdust? or would the acid in the ashes do more harm to the lumber in the house than the bugs would? I also have tons of free switchgrass and access to a grinder I have to do this on the cheap as i have no job and dont want to go on the govt doles. yea I know ,pride is a sin any ideas? I know there are some skin flints out there. what would you do?