Sona tube size for 12'x16' "saltbox" bathhouse-cabin ?
I intend to build a "saltbox" style guest cabin-bathhouse between our main cabin and the lake. This is an off the road place (Alaska) and I'd like advice on whether the six, 6" Sona tubes I hauled in this winter are sufficient for a pier type foundation. The building will have a metal roof, a woodstove, shower pan and screen, and moderate furnishings. It will not have a kitchen or toilet facilities. Any suggestions or references are welcome.