Buy some 1x6 and 1x8 rough sawn cedar boards and build your own beams. They will look much more "real" and if you want to screw an eye hook into one to hang a plant, etc, it won't pull out and fall on your head! In my area, a 1x6 12 foot long cedar board is $9 apiece. Also, there is less of a toxic fume hazard in the event (God forbid) of a fire.