Here's a practical tip you can use almost every time you fit a faux beam into place. Typically when you're installing beams on the ceiling, you want them to run from one wall all the way to the opposite wall. So you start by measuring (and re-measuring) the distance between the walls and checking to make sure each wall meets the ceiling at a right angle. Then you add about 1/8 inch to the measurement you've taken and carefully cut the wood beam to that length. This extra length ensures that the beam will fit tightly against each wall, conforming to any slight irregularity in the wall-to-ceiling joint. The polyurethane foam that the beam is made of can compress by this amount so it presses firmly against each wall to make a tight, gap-free joint. But how do you squeeze the beam into place without marring your nicely painted wall? As you shove the oversize beam into place, it can push hard enough against the wall surface to leave marks. This is especially true if you've applied your own paint or stain finish to the beam. The solution is simple: 1. Find a clean, heavyweight plastic bag that will fit over the end of the beam. Or cut a piece of plastic sheeting just big enough to wrap around the end of the beam. 2. When you apply the construction adhesive to the top edges of the beam, leave the last few inches of the beam with no adhesive. 3. When you climb the ladder or scaffold to fit the beam into place, take the plastic bag with you. 4. As your helper holds the other end of the beam in place against the ceiling, slip the bag over your end of the beam. Hold the bag so it doesn't touch the adhesive and get messy. Then shove the beam into place along the wall. The smooth plastic will help the beam slide into place and protect the wall from any rubbed-off paint or stain from the beam. 5. Once the beam is snugly in place, pull the plastic out.