Barn Wood Bunk Bed

When my sister’s grandson spends the night at her house, he sleeps on a cot that had belonged to our Grandpa in the 1960’s and some even-older relative before that. Over the past year and a half as we’ve been remodeling her house, I have spent many nights on it myself. And, though not what you might call an heirloom, it does carry a bit of family nostalgia and it’s a terrific piece of vintage portable ingenuity. However, its old-school spring frame leaves an adult person feeling like they’ve spent the night on Huck Finn’s river raft rather than sleeping in a bed! It’s time for a change and to satisfy the need for a ten-year old’s hideout and a more comfortable adult accommodation in limited space, a bunk bed has become the solution. 

Supplies

Various lengths of 1" and 2" thick recycled barn wood -we used oak and poplar.

Table saw, miter saw, circular saw, hand sander or sanding block. Safety glasses, tape measure, pencils, square, sandpaper. Drill, extra long 1/8" drill bit, clamps, wood glue. Kreg® Pocket Hole Jig, Kreg® pocket hole screws in various lengths.

Bucket, scrub brush, Borax®, water

Minwax® Polycrylic Flat Matte Finish, brushes, rags

Step 1: Select and Cut Wood to Length

My sister had a some barn wood stockpiled, but it wasn't enough for the entire cut list. Luckily, we had access to an inventory that our Dad had saved years ago and was still usable as he had always kept it covered. We had to work around some weather weakened areas and attempt to choose pieces that were close in thickness. Older boards are not the same dimensions as the boards we buy today and are not necessarily very consistent with each other or even from one end to the other of the same board. Speaking from experience, make sure to measure both edges and both ends!

The room the bed will inhabit is fairly small. So, even though the goal was a chunky bunkhouse look, the room required a design as compact as possible to leave my grand nephew some play space, yet, we still had to accommodate the 38" x 74" twin sized mattresses my sister planned to purchase.

To save some space, we designed the mattress rails, safety rails and ladder steps to fit flush in the corner posts instead of applying them to the surface of the posts. The steps are fitted into notches and the rails are half-lapped. This trimmed the length and width by at least 4" in both directions as the old 2" x 4" wood was actually 2" (in some instances, 2"+) thick.

Sort your lumber to better understand the lengths and widths you have to work with. We first ripped the wide 1" stock my sister had into rails and cleats using a table saw. Secondly, we carefully chose the longest 2" stock from our Dad's pile to cut the post parts to length. Finally, we cut the ladder steps from the remaining shorter pieces and the pieces that had weak or unsuitable areas to work around.

Vintage Wood Cut List:

8) 2" x 4" x 72" - 8 pieces will create L shaped corner posts

10) 2" x 4" x 39" -ladder steps

4) 1" x5 1/2" x 76" -mattress rails (we ripped our rails to 5 1/2" to maximize our material. You may need to modify your measurement based on your material and the mattress length)

4) 1" x 1 1/2" -mattress rail cleats

2) 1" x 4" x 76" -safety rails

New Wood Cut List:

2) 1/2" x 38 3/4" x 76" plywood mattress base

10-12) 1' x 4" x 38 3/4" slats

Step 2: Cut Notches and Half-Laps

I started by determining to set the ladder steps at 12" intervals up to 60". I measured and marked the intervals on four of the 72" 2x4s. Nearly all of the 2x4s were a full 4" so I cut all of the notches 4 1/16". Some of the steps were thicker than 2". I realized then that those might end up thicker than the posts, but it was designed to look like old bunkhouse furniture, so, no matter.

This step would have been more efficient had we had a sliding miter saw, but we did not. I cut the notches by first clamping the four boards together keeping the top edges even. I then set the circular saw to 1 1/2" depth and cut kerfs (blade width grooves) over approximately one half of the 4 1/16" width. I broke out the pieces and used the running circular saw to trim and smooth the tiny bits left behind after breakout by moving the saw side to side with the blade running. I cut the notches one half at a time to make sure there was enough area to balance the saw base. Take care to keep the base level so as not to dip the blade and gouge too deeply into the notch. You could do this clean up step by hand with a super sharp chisel depending on the type of wood you use and how much effort you wish to expend. Old oak is very hard. You could also use a plunge router if you have one.

After the ladder notches were cut, I measured and marked for the 5 1/2" wide lap cuts to accept the mattress rails and 4" wide lap cuts for the safety rails. I placed the height of the bottom rail at 12" and the height of the top rail at 58". Allowing for mattress depth, this leaves approximately 36" between bunks and 32" top bunk to ceiling. Adjust as you wish. In our design, the cut out area for the mattress rails were not true half laps as those boards were only 1" thick to start with. I only made the lap cuts on the posts and not on the ends of the rails. However, the safety rails were made of 2" stock and needed one half the thickness of each end removed to make a flush half-lapped joint. I removed a 4" wide x 1" deep area of material from each end of the safety rails. Remember to measure both ends of each board, as you may have to adjust the width of some of these lap cuts depending on the inconsistencies of the old lumber you are using.

I made these cuts the same way I made the earlier notches. This time, I set the saw at 1" and cut kerfs over one half of the marked areas. After breaking out the pieces, I once again, swiped the running saw from side to side cleaning up the remaining bits. Move the blade forward in small increments when performing this procedure and be sure to wear safety glasses.

Step 3: Sand and Clean

Our wood was rough cut and pretty dirty from laying around for years. After the parts were cut, they were swept as clean as possible, then washed with a Borax® and water solution to clean and to kill any insects that may have been hiding out in cracks and crevices. Borax® can typically be found in stores that carry a variety of cleaners and laundry soaps and supplies.

The parts were laid out flat to dry. We opted to lay them on the rails of a small trailer so they could dry from all sides simultaneously. You could also use saw horses, or scrap 2"x4". Anything to hold the parts off the ground and out of pooling water. When completely dry, all the surfaces were sanded just enough to knock off splinters and smooth out weathered areas then swept clean a second time.

Step 4: Pocket Holes in Rail Posts

Our design utilizes corner posts in an L configuration. The Rail Posts are the posts that will support the mattress rails. In other words, the posts anchoring the sides.

We used a basic Kreg® pocket hole jig for this step, but there are a number of brands to choose from. If you have never used a pocket hole jig, be sure to read the instructions carefully and familiarize yourself with the proper placement of the jig, how to set the depth collar on the drill bit and which length of screw to use for the thickness of wood you plan to drill into.

Use a square to align the jig and definitely use a clamp to hold the jig in place. Even with a clamp, the jig may twist slightly to the right as you begin drilling. Use a second clamp on the square if necessary. Lightly sand around each pocket to remove splinters and to evenly round out the opening. You can purchase and use a pocket plug cutter to make matching plugs that will hide the pockets, but we opted to leave them open.

Step 5: Assemble the Ladders

The vintage wood was not of consistent thickness or width. We made sure that the side that would be facing out was flush and didn't worry about the back side. A few notches had to be widened where the fit was too tight. Once all the ladder steps fit into the respective notches on the Ladder Posts, it was time to drill more pocket holes. This time, however, I found that the pocket hole jig did not work as I needed it to.

Having cut out the notches, there was only 2" of width left for the pocket hole. This was not quite enough width to accommodate the entire length of the pocket at the low angle of the proprietary jig. I needed a shorter, steeper pocket. To make custom angle pockets, I cut a 30º wedge from the end of a 2"x4" and shortened it to leave the low edge about 3/8" thick. I measured and marked for 2 holes at each end of each step. With the pocket hole drill bit in the drill, I held the bit against the wedge to maintain the desired angle and carefully drilled deep enough to accept the entire screw head.

Tip: Be careful with this procedure not to drill so deep the pocket will break through the side of your stock or to let the drill bit twist off your mark. Drill a few practice holes on some scrap pieces first.

Step 6: Complete the Corner Posts

With the ladders assembled and the Rail Post drilled, it was time to complete the corner posts. I planned it so the Rail Post would cover the pocket holes drilled in the Ladder Post. The pocket holes for the Rail Post remain visible. You could get a pocket hole plug cutter to make plugs to hide them if you'd rather not see the holes.

The barn wood was not perfectly even or straight as you may have guessed, so clamps were a definite necessity. Something I had not anticipated was the inability of the self drilling pocket hole screws to actually drill through the old, dry oak without so much force I was afraid of splitting the wood. I had to devise a way to extend a pilot hole through the pocket hole. I decided on an extra long 1/8" bit. Using a pocket screw as reference for depth, I added an 1/8" for sawdust and put a masking tape "flag" at the point I wanted to stop drilling.

Tip: Use a scrap to test the depth. Otherwise you may overshoot and drill through the face of your post.

I started at the top by drilling the first extended pilot and put the screw in immediately. That way, I could move the clamp and work my way down forcing the edges flush at each hole.

Step 7: Mattress and Safety Rails

Before attaching the mattress rails to the posts, we fixed a cleat to each one to hold slats later on. This was straight forward. The cleat was the same length as the rail. We used 1 1/2" pocket screws, but pocket holes were not necessary here. However, we did drill pilot holes and countersinks at an 1/8" to accommodate the screw heads.

Much to my annoyance, the mattress rails were the same as the ladder steps in that a couple of them were just too tight a fit. Rather than disassemble the posts to widen the lap notches, I decided to take an 1/8" off the top edge of each of the two offending rails. That worked out fine. We did the same here as with the cleat. Pocket screws in pilot drilled and countersunk holes. In hindsight, it would have been best to dry fit all the rails and their notches before the post assembly. Live and learn.

Lastly, the safety rails. Again, the same procedure as the cleats and mattress rails. Pocket screws in pilot drilled and countersunk holes.

Step 8: The Finish

There was some deliberation regarding whether to finish or not to finish. My sister decided she would prefer a finish to make cleaning and dusting easier, but not a finish that would change the look of the barn wood. We settled on Minwax® Polycrylic Flat Matte Finish. It is a water based product making cleanup very simple. If you look closely at the second picture, just above the bucket, you will notice a very faint change in color after application. However, once dry, there is next to no change in the wood's appearance.

Tip: I have used this product for multiple projects and typically brush it on. I have found that rolling it can create tiny bubbles that make it more visible. Perhaps not so much on rough cut wood, but my sister stuck with a brush just in case.

Step 9: Cut Some Slats

To wrap it up, slats or a sheet of plywood, or to be extra safe, both, are needed to support the mattresses. Our plan is to use 6) 1"x4" slats and 1/2" plywood for each bunk. As per the cut list, the slats are 39" and the plywood 38 3/4"x76". Depending on the thickness of your wood and its final fit, or the actual size of mattress you will use, these measurements may vary slightly. If possible, purchase the mattress first to be sure of its size and double check slat measurements at each position along the rail.

And, now you may be wondering how we're getting this very sturdy (code for sooooo heavy) bunk out of the garage and through the kitchen door, down a hall and around a corner into the room.... We'll be disassembling the rails, marking one end of each and its respective notch with numbers 1 through 6 for simplified reassembly once in the room.

My sister reports that her grandson is very excited about this new bed with its alluring top bunk. She expects he may only come down to eat!