Redwood is rot resistant, but can get splintery if you don't seal it
somehow. If you are happy with the looks of the PVC, I'd go with that,
much less maintenance.
I'm amazed that you've had to replace that often in an 11 year old home,
but then again, I live in a dry climate.
By the way, there are a whole bunch of people in another thread trying
to figure out how get rid of ants, so watch out :-)
Fair Pacific Bamboo
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