Several years ago, we replaced rotted columns on our porch with round permacast columns. These sit on 3' high square concrete-faced bases with spruce trim (columns are slightly smaller in diameter and required trim for aestheticsreason.) with an atteached ceadar shake faced wall topped with spruce planks). Caulk seals the seams at the bottom of the column base to the spruce trim and adjoining plank. The spruce trim has now rotted out from water collecting in the joinery seams, and needs to be replaced. We are looking for an appropriate replacement material recommendation- something loadbearing that can be painted white.