I don't know about the technical aspects of properly wrapping a porch column, or whether to use treated wood. However, before wrapping a porch column with real wood, I would be thinking about how to put a durable finish on the wood. My neighbor spent a small fortune having a custom wood garage door made. The door looked gorgeous for about a year, and then the finish began to fail. After three years, the garage door looked like crap (faded & peeling). Also, I would consider a vinyl or PVC wrap, if I could find one in a wood-look material that looks good. Some manufacturers (e.g. Georgia Pacific & CertainTeed) make nice synthetic wood-look sidings, but I don't know whether they make similar wood-look materials for wrapping columns. This post was edited by GypsyWaterfowl on Sat, Jul 27, 13 at 22:55

Wouldn't cladding outdoor wood beams in plastic just invite moisture infiltrating and getting stuck and then potentially causing rot? Agree about just painting or finishing with appropriate exterior paint/varnish. Leaving it as wood lets the beams manage moisture better (if they get wet, they can also dry out) and if rot does happen, you'll be able to see it and not have it hidden and festering under plastic cladding.

I'd suggest (and your neighbors will appreciate) warm (low-Kelvin), dark-sky lighting which illuminates the porch only to the extent necessary, doesn't shine into the yard or into neighbors' windows, and is turned on only when needed. Dark Sky > Outdoor Lighting Basics Dark Sky > Find Dark Sky Friendly Lighting

I agree with mie0782. Experienced continual seam-splits with our builder installed columns. Unfortunately exact match replacements were unavailable in PermaCast but the millman recommended painting the hollow interior before installing new ones. I used highway striping paint using an old towel attached onto a piece of conduit as a paint brush. Original columns began showing signs of failure within a year, replacements are still like new after a decade.