My wife wants an arched entrance to the front of the house -- and of course
I just say OK.

The arch will cover a span of about 72" and will be about 18" in height.
Okay no problem.

My question is -- Since this is an outside project and subjectto heart and
humidity extremes I am wondering about material to use. I thought about
glueing up cedar but that doesn't hold well -- at least from my experience.
Then thought maybe some glued up white oak might do the trick but I would
need to go find some -- the guy I normallly buy from is about 400miles from
here so not close enough for a weekend project.
Any thoughts about using exterior grade ply? I always dread using ply where
it is exposed to the weather.
If I cover the ply with a urethane will this help prevent decay?

Any ideas. Dummy simply says ok and now I need to figure it out. duh.

Thanks. Thom