Diy Wood Ceiling Beams . Use a miter saw to cut 4 boards to identical lengths (3 to construct the beam and 1 to attach to ceiling drywall / joist) lay one board flat and add wood glue to its sides. How much did our diy wood beam ceiling cost? Pin on Kitchen from www.pinterest.ca Make sure you used clamps to get as flat of a seam as possible. Roughen up the wood for a. Giving them that floating effect did that in my opinion.