It's a beautiful room . . . well, it's almost a beautiful room. Right now it's a good-looking but slightly bland room that needs a defining detail--like ceiling beams. Turn a cathedral ceiling into something that adds a more defined, established, slightly historic touch. The mere thought of installing wood ceiling beams makes your back and your budget ache. So let some off-the-walls thinking provide an on-the-walls solution: Styrofoam.
Measure the lengths of Styrofoam you'll need and the intervals at which you will place beams. For a flat ceiling, measure wall to wall. Mark the intervals at which you plan to install beams. If your source of Styrofoam can't supply the length you need, cut beams in shorter pieces first, then fit them together when gluing them in place. Mark your ceiling with enough guidelines to set your long or shorter pieces of beams in place; masking tape lines are easier to follow. For a pitched ceiling, allow an extra 6 inches of foam per beam. You'll be cutting small pieces to fill in angles between the ceiling and wall. If you want a rustic, hand-hewn look to your ceiling beams, allow an extra couple of feet to practice your hand-hewing techniques.
Measure the Styrofoam and cut it to size. You may be lucky enough to find prefab Styrofoam beams (this decorating strategy is not a tightly-held secret). If you find them, skip to Step 5.
Add some rustic wood-like effects if you like. Start on your practice piece and see what effects you can get with a table knife: cut small nicks, tap it with a hammer for a chisel effect or use the hammer to bang it flat into the Styrofoam. Try out what your sharp knife or open scissor blade can add. Empty out the gadget drawer--tablespoon/hammer, that waffle-cutter for the homemade french fries you don't make, pizza cutter--get creative. Once you've found your best techniques, apply them to your beams.
Stain or paint your beams or pieces of beams. If working with pieces, stain ends as well as the beams to avoid Styrofoam showing through. Begin with your practice piece so you know how much stain or paint will be absorbed by the Styrofoam with each coat. Let it dry thoroughly.
Attach the beams using wood glue. This is, of course, the most precarious part of the job, so do the following to avoid dripping glue and dropping beams. Coat the side of the beam that will attach to the wall with an even coat of wood glue. Set it aside to set partially dry--to the tacky stage. If assembling beams in pieces, apply the glue to the beam ends but don't join the pieces until you attach them to the ceiling. While that happens, apply a coat of glue along the line where the beam will go. Let the glue dry to the tacky stage. When the ceiling and beam glue are tacky, attach the beam to the ceiling with a helper. Moving ladders as needed, press the beam or beam pieces to the ceiling with dry sponges, two or three times every 5 to 10 minutes until you are certain of a firm hold. Repeat this until all beams are firmly in place.