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Don’t you think a fireplace helps make a room feel cozy? It also helps add that architectural interest and creates a focal point in any room!

I’m SO excited we’re finally getting our fireplace installed! It’s only been on the wish list for 5 years 😆 (At least something good is coming from our quarantine time…we’re getting things checked off our To Do list!)

Have you ever wondered how to make a faux wood beam mantel, or maybe even wondered how to make a floating mantel, or install one?

If you’re joining us from last week’s post, Part 1: How To Install a Fireplace Insert, welcome back! We’re excited to share Part 2: How To Make and Install a Faux Wood Beam Mantel. Be sure to join us for Parts 3 and 4, the following two Saturdays, to see how we will be finishing the fireplace.

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Before we dive in, here are the supplies that you’ll need.

Supplies Needed:

Before you begin, decide what type of wood you’d like to use and source the materials.

For the top and bottom boards of the faux wood beam, I went with a pine whitewood board. (1-in x 12-in x 8-in, about $19 each.)

These have a knotty texture and add a more rustic look. I don’t mind having a knot in the wood here and there, so these were great for the top and bottom surfaces and were a little cheaper.

On the front of the faux wood beam mantel, I went with a select pine whitewood board. (1-in x 10-in x 8-in, about $25.)

The select boards are a premium solid pine with smooth surfaces on all edges. I chose this board for the front edge because I didn’t want the focal point of the mantel to have a large knot right at eye level.

When choosing your boards it’s important to look for any warping. Try to get the boards as straight as you can.

An easy way look for warping is to hold the board on end and look down the length of the board. (See picture above.) This board is a little warped, but it was one of the better choices. (And the faux wood beam still turned out beautifully!)

Click on the video below to see step by step how this entire faux wood beam mantel is built.

Faux Wood Beam Mantel Step 1: Measure all boards and cut to size

Once you get all your lumber home, the first thing you’ll need to do is measure each board and cut to size.

The dimensions of our faux wood beam mantel are 10.75″ deep x 7″ tall x 6.5′ long.

Step 2: Miter Edges To Create A Seamless Joint

Adjust the blade on the table saw to a 45° angle to cut the mitered edges.

Making this faux wood beam mantel with a mitered edge sets it apart from other do it yourself versions I’ve seen. The mitered edges will allow you to assemble your faux wood beam with seamless joints!

After all, we’re going for the look of a real beam, so we don’t want to see any seams where we’ve put it together.

(Otherwise it will look like a large piece of wood that you’ve secured together.)

I’m such a visual learner! I hope this labeled picture above is helpful. You’ll notice that we have the top and bottom boards stacked on top of each other. Using a pencil, draw an angled line in the direction of the mitered cut.

Notice that the front edges of the beam will be mitered, while the back edges will remain straight. The straight edges will be flush with the wall upon installation.

After each of the boards have been cut to size (to both the correct width and length), miter all edges where the faux wood beam will join together.

(See image below for a better visual of which edges will be mitered and which will have a straight edge.)

Basically any edge that will be on the back of the faux wood beam will have a straight edge so it will be flush with the wall.

Referring to the picture above, the board on the left will be lifted up toward the right to form a 90° angle where each of the mitered edges will meet.

This will be the top of the faux wood beam mantel.

Repeating this with the board on the right, it will be lifted up toward the left to form a 90° angle where each of the mitered edges meet.

This will be the bottom of the faux wood beam mantel.

The middle board will be the front edge or surface of the mantel.

(Essentially we’re building a hollow box with no lid. You’ll see why we’re not building an enclosed box when we get to installation.)

PRO TIP: Be sure to label the inside surface of your boards. This will make it so much easier when assembling the faux wood beam! We labeled which edge would be flush to the wall as well as which board was the top and bottom, and also marked the inside area of the beam.

Each of the end pieces of the faux wood beam have been cut to 10.75″ x 7″.  Then miter the top, bottom and front edge of the end pieces. Leave the back edge straight so it will be flush with the wall.

PRO TIP: Securing the fence into place will help ensure you get nice square cuts. And it will save you time from stopping to measure each time you cut. Measure once, secure the fence and make all mitered cuts.

Step 3: Assemble Faux Wood Beam Mantel

To assemble the faux wood beam mantle, use wood glue and a pneumatic brad nailer with 2″ brads.

This step was especially helpful with a couple extra sets of hands. After applying glue all along the long mitered edge, two of us held it into place while the third secured it into place with the brad nailer.

Be sure to wipe away any excess glue from the seams with a damp washcloth before moving onto the next board.

Complete this step to secure all of the mitered edges together to create the seamless joint.

First secure the front edge of the faux wood beam to the bottom piece. Then secure the top piece to the front edge. Followed by each of the two end pieces.

Once all edges have been secured together, you’ll have a box with 5 sides.

Step 4: Apply Wood Filler & Sand Joints of Faux Wood Beam

Faux Wood Beam Mantel

Once the box has been assembled and the wood glue has dried, apply Plastic Wood All Purpose Wood Filler to every joint/seam, and nail hole.

This particular filler is a great option if you’re intending to stain your faux wood beam. It acts and looks like real wood, and will take on the color of the stain.

If you’ll be painting your faux wood beam, you could also use Dry Dex Dry Time Indicator Spackling. This will go on pink and dry to a white finish. It will accept paint well, but won’t take the color of a stain.

Faux Wood Beam Mantel
Faux Wood Beam Mantel

Follow the directions per filler you’re using. The plastic wood filler is a little different to apply than the dry dex spackling.

Usually when applyling spackling, less is more. You’ll apply just what you need and scrape off any excess which will make the next step of sanding a lot easier.

To apply the plastic wood filler, you’ll need to apply it a bit thicker.

The directions said to apply liberally, and while attempting to scrape off the excess, it actually pulled everything right off! More is better with this type of filler.

A small putty knife worked well to apply the filler. At some points, my finger even worked better to push the filler into the joint! You may need to play around a little to see which method works best for you.

Faux Wood Beam Mantel

Once the wood filler has completely dried, use a palm sander to remove the excess filler.

I used a medium grit sandpaper to remove most of the filler since it was a bit thicker.

 Swap to a fine grit sandpaper for the final sanding. This gave me a nice smooth finish on the faux wood beam.

Step 5: Apply Stain & Sealer

After the beam has been sanded, wipe away all the dust with a wet washcloth and allow the wood to dry.

Apply a stain of your choice.

I wanted our faux wood beam mantel to look natural and have a little whitewashed and weathered finish. The original pine color was a little too light for me.

I played around with a few different stain colors on some scrap pieces from building the mantel. I ended up using my own little recipe of stain.

First, I mixed 2 parts of Minwax Golden Oak 210B with 1 part Minwax Classic Gray 271. Then I applied this mixture on the faux wood beam with a cloth. I immediately wiped off any wet stain. I didn’t want this to get too dark. Finally, to achieve the desired weathered look, I added a layer of Varathane Sunbleached over the beam once the first mixture was dry.

Faux Wood Beam Mantel

Applying the stain can be done in a couple different ways. You can use a paint brush to apply in long even strokes, going with the grain of the wood. Or you can use an old cotton rag to simply wipe it on.

The brush will give you a finish that is a little more neat. Using the cloth (as I did with the first layer of stain) can leave some areas of blotching or other imperfections.

As I was going for a more weathered and worn look, I didn’t mind having these imperfections from using a rag.

Faux Wood Beam Mantel

Work on one surface area at a time. It’s best to play around on a scrap piece of wood first to test the coloring. The longer you allow the stain to penetrate the wood, the more color will be absorbed.

With the stain recipe I used, and the look I was going for, I applied the stain and wiped away all the excess with a clean cotton cloth almost immediately after application. It gave me just the right amount of color I was going for.

Faux Wood Beam Mantel

After allowing the first layer of stain to dry to touch, I applied the Varathane Sunbleached stain with a soft bristle paint brush. For this layer I wanted a nice even coating.

Faux Wood Beam Mantel

Again, I let this layer of stain sit on just for a minute or two and wiped away the excess. This brought out a little bit of the first layer of stain coloring and the second layer accentuated the grain of the wood.

Follow the directions for dry time per the specific stain you’re using. Once the faux wood beam has completely dried, a sealer can be applied.

I used the Varathane Triple Thick Polyurethane with a matte finish.

The first time I  used this product was on the Hidden TV Cabinet we made and I LOVED it! I’d never used this sealer before but it has a couple of features I really like!

First, application is really easy. Simply apply with a soft bristle paint brush. The softer the bristles, the less chance of having visible brush marks.

Second, it’s made with an advanced self-leveling formula, and 1 coat equals 3 coats to other sealers! So you’re getting a lot of protection out of 1 layer which means less product used, and less work!

And third, it has a clear matte finish. Usually I use a wipe on poly with a satin finish which adds a little sheen to the finished piece … but having a clear matte finish on this faux wood beam mantle makes it look even more like a thick wood beam!

It’s also a water based sealer so clean up is really easy!

Faux Wood Beam Mantel

For added protection I applied 2 coats of sealer, allowing it to completely dry before reapplying. When applying be sure to use long even brush strokes following the grain of the wood.

This gave me peace of mind that there wouldn’t be any small visible brush strokes.

Allow sealer to completely dry before installation.

Installing Faux Wood Beam Mantel

To install the faux wood beam mantel we first built a cleat which will be secured to the wall.

Using scraps of 2 x 4’s we cut a board to length so it would fit just inside of the faux wood beam box we made.

Then we added 3 smaller scraps to each and and one in the middle for support.

Once the height placement of the mantel has been determined, secure the cleat into studs using long screws and a level.

After the cleat has been secured to the wall, the faux wood beam mantel will slide onto the cleat. The mantle will then be secured to the cleat by drilling long screws down into the cleat from the top of the mantel.

You’ll want to drill the screws into the cleat as close to the back of the mantel, by the wall, as you can. If possible, secure the screws deep enough into the mantel that they are below the mantel surface. Then you can use a little wood filler to cover up the screws. Touch up those spots with a little stain and sealer, and you’ll have a beautiful floating mantel!

Although, we didn’t stop there! 😆 Join us next Saturday to see how we built some pretty amazing corbels! (Which I might add are completely for aesthetics since the mantel is completely secured and supported without the corbels.)

So what do you think? Is this a project you’d like to try? Would you have built or installed it differently? We love hearing from you, please share in the comments below.

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And as always here at Sunny Side Design


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This Post Has 2 Comments

  1. Renae

    This looks great. Do you have a picture of the full mantle? I’d love to see the big picture.

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