DIY Built-in Bunk Beds: Looking to add built-in bunk beds to your child’s room? See how we built these DIY bunk beds with bookcases in our girls’ shared bedroom. Below, I’ll share how we designed the room, how we built the bunk beds, all the materials we used, and what tools we found the most useful!
DIY BUILT-IN BUNK BEDS
We had a little extra time over the winter holidays this year that we finally decided to pull the trigger on one of the most ambitious projects we have undertaken yet – built-in bunk beds and bookshelves in the girls room! Bowie and Brooke had already been sharing the room for a couple of months; but, with Bowie in a full size bed, and Brooke ready to move out of her crib we knew we needed to make a few changes.
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Our primary goal was for both girls to have equal space in the room (so nobody felt cheated) and at the same time give each of them a space with some privacy that was their very own! We also wanted to add some additional book and toy storage to the room while preserving as much open floor space as we could for the kids to play. And now there’s so much space for… activities. (any other Step Brothers fans out there?) 🙂
Room color: BM Romance Pink 25% strength and BM Simply White on trim and bunk bed
The design we settled on was built-in bunk beds with curtains centered along the longest wall in the girls room flanked by built-in bookshelves on either side. This way each girl could have her own bookshelf to keep her books, toys, piggy bank, etc. Down the line, if the girls need desks, we can turn their bookshelves into them. But for now, the girls (ages 7 and 3) just need a space for books and toys!
- MDO Plywood ¾” thick 4’x8’ sheets $65 each 5 sheets
- Select Pine 1x4x8 - 6 boards
- Select Pine 1x6x8 - 8 boards
- ½” MDF 4x8 sheet - $21 - 1 sheet
- ¾” MDF 4x8 sheet - $30 - 1 sheet
- Door Stop trim ripped down to ½” 7ft long - 6pcs 2x4x8’s - 8 total pcs
- Wood glue
- 1-⅝” Drywall Screws
- 3-⅛” cabinet screws
- 1-½” 18ga brad nails
- Sandpaper 120 grit
- Primer- buy at a paint store for best price
- Painter's Tape
- Plastic sheeting
- Paint filters
Building the Base
We started by building a base platform out of 2x4s that the bottom mattress would sit on. This was a simple frame screwed together with deck screws.
We set our stud finder to find all the studs on the wall and marked them with blue tape (this is a nice trick because it lets you visually see right where the studs in the room are). We carefully centered the base platform in the room and secured it to the wall with 3-1/8" long cabinet screws.
Cabinet screws are unique because they have a large flat washer-head that will hold the 2x4 tight to the wall without pulling themselves deep into the wood crushing the wood fibers. We also made sure to have one of us standing on the base to compress the carpet and padding as much as possible while screwing the base to the wall. If you were building this on top of hardwood or subflooring you wouldn't have to worry about this.
Ceiling / Walls
The next step was to attach cleats to the ceiling joists. These cleats are used to attach the walls and front of the bed. Again we used the stud finder to locate the ceiling joists and used our laser level to carefully align the ceiling cleats directly above the base platform.
This was to ensure the walls and front of the bed were be straight and plumb. We made the cleats out of 2x4 material like the base and attached them to the ceiling with the same 3-1/8" long cabinet screws.
We made the wall panels of the bed out of ¾” thick MDO plywood. MDO stands for Medium Density Overlay. This is a high-quality plywood with a thin resin-treated fiber layer applied to both sides. It is smooth, uniform, easy to paint, and produces a great looking finish. It’s a little more expensive than regular plywood but with so much surface area to paint, it saves substantial sanding and prep work so we decided it was worth it. In the end, we are very happy we chose to use the MDO and would definitely recommend it.
Once the walls were up we cut and attached the two strips of plywood that would become the front "columns" of the bunk beds. These are also 3/4" MDO plywood and were glued and screwed to the wall panels, base, and ceiling cleat with 1-5/8" drywall screws.
Height of upper bunk
Typically when we do a DIY project of this scale we would design everything ahead of time - usually in a 3D CAD software such as Sketch-Up or Fusion 360, both of which are free for home use.
This project was a bit more “figure it out as we go” which for some of the details it really needed to be as we built it right in place. The next step was to determine the height of the top bunk and the overall proportions of the front of the bed. We old-school sketched the bed out to scale on graph paper and used that to roughly approximate the height of the top bunk.
Our goal was to have the distance between the top of each mattress to the opening in the front of the bunk to be roughly equal. We knew Brooke would be on the bottom bunk so it could have a little less headroom than the top bunk--but we still wanted to make sure a grown-up would fit comfortably in for storytime. Once we figured out the heights we drew them in on the graph paper - and this became the template for the rest of the build!
Next, we cut the front cross brace that would support the front long edge of the top bunk. We first clamped it in place to get our first real visual of what the bunk beds would look like. After a little more measuring and fine-tuning we glued and screwed it permanently into place.
This part of the bed needed to be extra strong and stiff so we used 2 layers of ¾” MDO plywood glued and screwed together. Above, you can see the full 1.5-inch thickness of the front of the upper bunk. This thing is going nowhere!
Next, we added the front face of the lower bunk. This was also 2 layers of 3/4" MDO glued and screwed to the base platform. We also used pocket hole screws to attach it to the sides of the columns - but in hindsight, these were probably not really necessary and could be omitted...
This part of the bed didn't need to be 2 layers for strength (because the bottom bunk platform just rests on the ground, but it kept the design consistent with the upper bunk which made trimming it out easier later on.
At this stage, we spent a lot of time thinking about how we would trim out the details on the bed. Specifically the proportions of the panels and the widths of all the trim pieces that would be used to cover the edges of the plywood around the bed openings.
We decided to prototype the width of the side “columns” and the proportions of the recessed panels by cutting out cardboard templates and drew in the size/shape of the recessed panels. We tried 3 or 4 different sizes and proportions before we found one that felt just right. We think it’s so important to make full-size prototypes of details like this when we can. You can see one of the cardboard templates on the floor in the picture below.
The inspiration for the details on the bed was from old classical fireplace mantels. We wanted the middle portion of the bunk bed to look like one continuous horizontal design element only interrupted by the opening into the top bunk. We think this makes the bed look a little more formal and built-in. We’re really happy with how it turned out!
The bottom bunk mattress sits on top of a couple of sheets of ¾” MDF that were cut to fit directly on top of the 2x4 base we made at the beginning. For the top bunk mattress, we used sheets of the same ¾” thick MDO plywood we used for the bed walls.
Plywood is much stronger than the MDF and since it could be supporting a couple of kids at a time we wanted it to be as strong as possible. These upper bed supports rest on top of four hardwood cleats that are screwed around the perimeter of the mattress. The plywood supports are then screwed into these cleats from the top which makes the whole assembly incredibly strong and rigid!
The recessed panels were created by attaching pieces of ½” MDF on top of the MDO plywood to create the raised areas. The wood for the molding detail came from some stock “doorstop” moldings from the home center that I ripped down to the thickness of the MDF. Mitering all these corners took some time especially since the miter saw was 3 floors down in the basement - measure twice, cut once!
Above, you can see hubby adding the mitered moldings to the inside edges of the 1/2" MDF "recessed panel".
The rest of the trim is simply cut from some knot-free "select pine" boards from the home center. Poplar would be a great choice too. Most of the trim was attached with 1-½” long 18ga. brad nails and wood glue. Some of the larger pieces that would see a lot of heavy use from the kids (like above the bed openings and at the top of the ladder) I countersunk drywall screws for extra strength and later came back and filled in the screw heads.
The crown molding at the top of the bed and bookshelves is an important visual element. We ended up buying two different sizes of crown molding at the home center because we were not sure which would look best. We ended up using the largest size we could find - and we were surprised that once the crown was all the way up in the air it looked much smaller in scale than it did when holding it at eye level.
This was actually the first time I had ever installed crown molding. After watching a few online tutorials and CAREFULLY measuring and marking for cuts we were pretty successful with only a couple of screwups.
One key though we found is using superglue and spray activator to quickly glue the “show” miter joints together. These are the outside corners that are most visible once installed and using the superglue to pre-assemble these joints meant that these joints would be perfect and tight.
Once the crown was up we started to prep for paint. The old adage that a good paint job is 90% prep and 10% paint is true! Step 1 is sanding. It was important to make sure there were no sharp corners or edges since the kids would be climbing all over this bed.
Flat areas were sanded smooth with the random orbit sander and 120 grit sandpaper. Edges were eased by hand with 120 grit and a sanding block.
After vacuuming up all the sanding dust it was time to spackle all the nail holes and screw heads. I used a basic latex spackle I found at our local hardware store. It goes on smoothly and dries fairly quickly. Once dry it can be sanded flush with the surface. I also had a bunch of exposed plywood and MDF edge grain along the sides of the bed that needed to be spackled so they wouldn’t show after paint.
After sanding smooth and vacuuming again I found a few nail holes I forgot, and a few other imperfections that needed to be spackled and sanded again. So one more round of spackle/sand and we could prep the room for spraying.
We chose to spray these built-ins for a couple of reasons. First, there was a LOT of surface area to cover AND an airless sprayer can lay down a lot of paint quickly. Second, there were a lot of little details that would have required a lot of careful hand-brushing. Do-able, but time-consuming.
Finally, we really wanted thede built-ins to have that smooth uniform semi-gloss finish you can really only get from a sprayed finish - especially on the large flat panels where you would never be able to hide the roller stipple or brush marks.
To do this we needed to mask off EVERYTHING. We made the mistake once of spraying our DIY mudroom and not sealing it off from the rest of the house perfectly and there was fine white dust everywhere. So for this room, we laid down ⅛” hardboard on the floors and ran plastic sheeting from floor to ceiling on all walls that weren’t being painted.
We SHOULD HAVE put a box fan in one of the windows to exhaust air and dust OUT of the room as we were spraying. Since it was early January in Wisconsin and near 0 degrees F we just left it sealed off and it was OK - but it would have been much less dusty with an exhaust fan.
The sprayer we chose to go with is the Graco Magnum Project Painter Plus. We chose this over the smaller HVLP sprayer we have used for all our doors and other projects primarily because the Airless can lay down A LOT of paint QUICKLY. In fact, it can actually put out TOO much paint if you use the wrong tip.
The key we found with this particular sprayer was to NOT use the stock spray tip that came with the unit. The stock tip is OK but it puts out way too uch paint for a detailed interior project like this (i think it would be great for painting a fence or a garage door or shed). Instead, I went with a Graco Rac-X 310 tip. You'll also need a Rac-X guard.
These are professional grade, fine finish tips. They come in all kinds of different sizes and spray patterns. We used size 310. This tip puts out just enough paint that you can still cover some ground on the flat sections but little enough that you have enough control on the detailed parts that there is less risk of a run (although I did have a couple of runs anyway but that was operator error).
Once the room was all taped off and the paint sprayer was ready to go I gave everything one last wipe down with a cloth and sprayed the one layer of Benjamin Moore Sureseal Latex Primer. A light sanding with 120 grit after it was dry is super important to smooth out any raised grain or spots of overspray and leaves a nice smooth uniform finish.
It’s also the time to go back and fill in any nail holes or caulk any gaps you may have missed. It’s amazing how they appear much more obvious once the primer goes on!
Finally we applied 2 top-coats of our signature Benjamin Moore Advance Semi-Gloss in Simply White. I did not sand between coats, but if there was a place that needed touching-up you certainly can.
After 6 months, we are still loving the bunk room! The girls absolutely adore their own little nooks and we’ve found each girl having their own private space to be really helpful in having two sisters peacefully share a bedroom. Each girl pulls closed their curtains each night, and they each feel like they have their own little nook! Now, we just need to figure out how we are going to make an “equal” room for our son and youngest daughter down the line 😉 See the full reveal here: Girls Bunk Room Reveal
Related: See how we made the DIY Cornice Board here