The first step to building your own banquette is to determine the dimensions. Measure the floor in the intended area to find the length. Then, use a comfortable dining chair as your guide to find the measurements for the proper height and seat depth. If it makes your work easier, sketch out a five-sided box (the top will remain open) and transfer your measurements to the illustration to use as a guide when cutting and assembling the box.
Transfer your measurements to the 4’ x 8’ sheets of 3/4” birch plywood that will be used to build the banquette’s box frame. Rip the plywood down according to your measurements using a table saw. This is much easier with a helper to support the weight of the wood while you guide it through the saw. Shorter cuts may be easier to make using a handheld circular saw. When you’re done, you should have five pieces of wood: front, back, bottom and both sides.
Assemble the box frame by first attaching the front panel to the bottom. Use wood glue and finish nails to hold the unit together during assembly. Add the back panel next and then the two side panels (Image 1).
Once everything is assembled and fits together properly, reinforce the structure by screwing all the pieces together with 1-1/2” wood screws (Image 2). If you plan on covering the banquette with beadboard, do not worry about the screw heads being visible. If you decide to paint or stain the bench, you will want to counter-sink the screws enough that you can cover over the heads with wood filler.
Add braces at each corner for extra support and to hold up the top frame. Cut scrap pieces of 3/4" plywood at two 45-degree angles to create a triangle. Make sure it fits snuggly into the corner flush to the top of the vertical pieces. Attach with wood glue and screws.
Frame the top of the bench using 1x4 poplar (Image 1). Use a miter saw or a circular saw to cut the wood to length. Attach the framing with wood glue and finish nails (Image 2). The purpose of the framing is to add strength to support the bench top and the weight of people sitting upon it.
The side of the bench that will be against the wall will need an extra top frame piece to hold the piano hinge and bench top. Cut another 1x4 to the same dimension as the back piece and fasten it on top of the other with glue and finish nails. If your banquette will have a filler piece that won't hinge open -- for instance to fit in a corner or to go around post -- combine the filler pieces with the top piece of the framing for a more seamless look. If you do have one of these non-opening top pieces, be sure to make them the same size as the opening piece including additional width for the hinge. Also, you'll want to round-over the front edge of the bench top to make it more comfortable.
Bring the bench into the house and set it in its permanent location. Use a 4' level to make sure the top surface is level. Use shims if necessary to achieve a level position. Then attach it to the wall studs from the inside of the bench using 3" wood screws.
Installing beadboard is a great way to decorate the face of the bench. Simply cut the beadboard to the appropriate height, apply construction adhesive to the back (Image 1), and install it to the face of the bench (Image 2). For added strength, add a few finish nails to the beadboard, but make sure the nails are short enough that they don’t pierce the open inside storage area of the bench (Image 3). This can be done using 4' x 8' sheets of beadboard, but it’s easier to install using the snap-together modular wainscotting material.
Alternatively, if beadboard doesn’t fit the look you’re hoping to achieve, you can also paint, stain or even tile the front of your benches.
The bench top will have a hinged door to provide access the storage area inside the banquette. The opening should be large for easy access to the storage area inside, but to make the seat more stable, your door should not extend more than an inch over the sides of the bench. The front edge should overhang just enough so it is easy to lift up. Trace the dimensions for your door on the top of the plywood. Make sure to calculate the size of the hinge. Cut the plywood and then round egde of the front of the seat with a router and sand it smooth. Prime and paint as desired. Seal with polyurethane to protect the finish.
Dry fit the bench top and filler pieces to make sure the size and placement are correct. Use wood glue and finish nails to attach non-opening bench top pieces.
A piano hinge is a long, continuous run of hinge commonly sold in lengths up to 6 feet. It is the best kind of hinge to use for this type of installation because it provides consistent support for the door and will help with weight distribution when someone is sitting on the banquette.
First attach the piano hinge to the side bench top, making sure that the hinge stays perfectly flush with the edge of the door. Use a nail, screw or an awl to punch small starter holes into the back portion of the storage bench where the hinge will attach. Then use a screw gun to run 1-1/4” wood screws into these starter holes, firmly attaching the hinge to the door.
To dress up the banquette and hide the unfinished plywood edges of the top, wrap the face of the unit in decorative baseboard. Use wood glue and finish nails for the install. To give it a more built-in look, use the same baseboard that is in the rest of the room.