How To Make Faux Beams From Foam Insulation Pieces

Adding real wood beams to your home is an expensive undertaking and not always structurally realistic, as the beams are quite heavy. Create the same look by making your own faux beams out of XPS foam insulation board. Making your own beams costs far less than installing the real deal, and it's a fun project that doesn't require professional-grade tools or building permits.

Making the beams requires foam insulation board, such as the type used for home insulation projects that's sold in big-box home improvement stores. It's not the same as the stiff white foam often used for fillers in shipping, and it won't crumble into tiny specks. XPS foam insulation board comes in 4 x 8-foot sheets, and it's easy to cut with a saw or to score with a knife and a straightedge and then snap to size. Pieces hot glued into a C-channel shape become the beams, which you scrape with a wire brush to create a wood grain texture and then coat with your favorite shade of brown.

1. Cut the Foam to Width

Cut or score and snap the foam to the desired beam width, such as 6 inches wide. Cut one piece for the bottom-facing portion of each beam as well as one piece to sit vertically on either side of every beam, as you're essentially building a C-shaped channel that looks like a beam once installed. The side pieces could be the same width as the bottom piece or as deep as you like depending on the desired look of the beam. The inner channel needs to be at least 3 1/2 inches wide so a 2x4 fits inside. The bottom foam piece should be 1 inch wider than the 2x4 (or 2x6 if you prefer) on either side if using 1-inch-thick foam board. In other words, the real board should fit snugly inside the C channel with no gaps.

2. Glue the Foam Planks Together

Hot glue the pieces together to make a long C-shaped channel, such as an 8-foot-long one to span 8 feet across a section of ceiling. The side panels sit atop the bottom panel, and the edges must be flush. Allow the glue to set for 30 minutes or as recommended on the glue stick package.

3. Create Faux Grain Texture

Create the wood grain look by scraping lengthwise across all outer sides of the beam with a wire brush, such as a grill-cleaning brush, several times to create grooves. Repeat the process on the edges and then rasp the edges and corners a bit to round them out. This is best done outdoors and while wearing a dust mask to avoid breathing in tiny particles.

4. Paint the Beam

Paint the outside of the beam with brown latex, chalk, or acrylic paint. For a more realistic look, dab on bits of a slightly lighter or darker brown depending on the desired look and then go over the wet paint with a dry brush in the direction of the grain.

5. Adding More Faux Grain (Optional)

For a pronounced grain effect visible from afar, apply a slightly darker coat of paint using a mix of 1 part translucent glaze and 1 part acrylic or latex paint. Run a rubber wood-graining tool across the wet glaze mixture, rocking the tool back and forth as you move it to create grain variations. Allow the glaze to dry completely before handling the beams.

6. Attach Real Board to the Ceiling

Securing the faux beam requires a 2x4 or even a 2x6 depending on the width of your faux beam, cut to the length of the faux beam. Attach the board to a ceiling joist exactly where you plan to install the beam using wood screws and a drill with a Phillips screwdriver bit. The wood screws should be about 2 inches long or long enough to go through the thickness of the 2x4 and into the ceiling.

7. Attach the Faux Beam

Enlist friends to stand on ladders and hold the beam up over the board so the hollow part of the faux beam touches the ceiling. Run 2-inch wood screws through the sides of the faux beam every 2 feet or so into the board attached to the ceiling. Use a delicate touch to avoid driving the screw too far into the foam; it should sit as flush as possible with the outside of the foam as it would in a real board. Black or brown screw heads look less obvious than silver ones, so pick the color that best matches the paint.