I am needing to construct a room with a concrete floor and walls. I was hoping someone would have some ideas on how to get that look. I was hoping to just start with standard luan flats as a base. I would like a weathered water stained type look to the walls.
Cool. That being the case, I think you should take a trip to your local Lowes or Home Depot. I'm pretty sure there's a spray-paint that'll do the trick. I'm not sure what you should paint it on. Styrofoam, maybe? Drywall maybe?
I don't have any tips because I am not a scenic artist, but
I can tell you from experience than a good scenic can make
any luan flat look like anything you want with paint, time
and talent. If there is a theater near you or a university
with a theater department I suggest contacting them.
Gray basecoat with a texture in it (the sand stuff, and while still wet, scrape with a grooved trowel maybe), then some colored treatments in broad but subtle strokes can break up the evenness of the color... then age it using watered down black paint in the corners and allowing it to drip on its own.
test paint stuff to figure out the techniques and colors that will work best or you.
Youtube is your best friend here, that's where I have found these types of things in the past.
Oh, yeah directorik makes two good points -- first, that you should contact a local college. Lots of skilled people looking for projects to join. Also, by pointing out the fact that he is not a scenic artist, that reminds me that I should've qualified my statements with the fact that I am not, either. I've done plenty of things DIY, and I was just thinking aloud.
knightly also makes a very good point -- lots of DIY stuff to be learned on youtube. And if what you're looking for isn't there, I'll bet there's a written tutorial somewhere on the internet.