Build It | Simple Bookshelf from Stair Treads

Homeowners who want to add storage space to their households without buying new supplies or lumber should consider repurposing their old stair treads. Stair treads can make for sturdy and attractive bookshelves, and you can complete construction of this new piece of furniture in just a few simple steps. Learn how to build and finish a simple bookshelf from stair treads in the step-by-step guide below, and watch the video above for tips from This Old House expert Tom Silva.

Materials Needed to Build a Bookshelf

Gather the materials below before you begin your project:

• 1/4-inch Luan plywood for the back
• 3 1/8-inch trim head screws
• 5d box nails
• Paint
• Primer
• Sandpaper
• Stair treads (5/4-inch thick pine)
• Wood glue

Tools Required to Build a Bookshelf

You’ll need the basic tools below before you begin construction:

• Chisel
• Circular saw
• Clamps
• Drill/driver
• Hammer
• Hand plane
• Straight edge
• Square
• Utility knife

Preparing the Stair Treads of the Bookshelf

Stair treads serve as the foundation of this bookshelf project. Their sturdiness and pre-finished edges make for an attractive, long-lasting piece.

Cut the Treads to Size

1. Measure and mark the length you want for your shelves.
2. Use a straight edge to guide your circular saw and cut the treads to length.
3. Leave two treads at their full 48-inch length for the sides of the bookshelf.

Rip the Treads

You’ll need to rip down the treads to create a finished look and accommodate the back panel. Follow the steps below.

1. Rip each shelf board down by 1 1/2 inches using a straight edge and circular saw.
2. Rip both side pieces down by 3/4 inch using the same method.

Stair treads provide a tasteful finish, and contain interesting features such as bullnose edges. These allow you to achieve a polished look without specialized woodworking tools. 

Creating Rabbet Cuts

Rabbet cuts allow you to seamlessly integrate the treads’ plywood backs into your design. Follow the steps below to make these cuts:

Side Piece Rabbets

1. Set your circular saw to a 1/4-inch cutting depth.
2. Use a straight edge to mark the width of the cut.
3. Make the first pass with the saw.
4. Adjust the straight edge slightly and make a second pass to remove more waste.
5. Clean up any remaining material with a utility knife.

Top Piece Rabbet

The top piece of your structure requires a stop rabbet, which doesn’t run the full length of the board. Follow the steps below to create this:

1. Start and stop your saw cut 1 inch from each end of the top piece.
2. Clean up the stop rabbet and square it using a chisel.

Rabbet cuts secure the back of the plywood without exposing raw edges. These cuts allow the back panel to nestle naturally against the sides and top, which makes the bookshelf especially stable.

Laying Out the Shelf Positions of Your Bookshelf

You must properly lay out your bookshelf to get the shelves in the correct positions. Follow the steps below.

1. Place the side pieces back to back with the inside faces up.
2. Position a 1×4 beam as a toe kick at the base of your structure and mark its location.
3. Place the first shelf piece flush against the toe kick and mark its position.
4. Measure 16 inches from the top of the first shelf to the bottom of the second shelf.
5. Mark the top and bottom of each subsequent shelf. Maintain the 16-inch spacing.

Bookshelf Assembly Process

After you’ve cut and marked all of your pieces, you can construct your bookshelf. Follow the steps below. 

Attach the Shelves

1. Pre-drill holes on each side piece between the shelf location marks.
2. Align the shelf with the rabbet cut and your marked lines.
3. Secure each shelf using three 3 1/8-inch trim head screws per side.

Install the Toe Kick

1. Position the toe kick using scrap pieces of stair tread as spacers.
2. Secure the toe kick with screws on each side.

Finish the Top

Follow the steps below to match the bullnose edge of the stair treads:

1. Mark the center of the nosing, and measure the distance to its back on the top piece.
2. Use a hand plane to round the edge. Match the profile of the stair tread nosing.
3. Attach the top piece to the bookshelf using trim head screws.

Trim head screws minimize the size of the visible holes, which makes for a more seamless appearance. You should fill any such holes with wood filler before you paint.

Adding the Back Panel of the Bookshelf

The plywood back adds stability and prevents the bookshelf from racking. Follow the steps below to add the back panel:

1. Cut the 1/4-inch Luan plywood to fit the back of the bookshelf.
2. Align it within the rabbet cuts on the sides and top.
3. Secure it using 5d box nails and a hammer.

Inserting the back panel tightens the overall structure of the bookshelf, and allows it to endure more weight without warping. This inhibits the lateral movement of the structure, and extends the lifespan of the bookshelf.

Finishing Touches to Your Bookshelf

Follow the steps below to complete your bookshelf:

1. Sand all surfaces thoroughly.
2. Apply primer to all surfaces.
3. Fill in any visible nail holes with wood filler.
4. Once the surfaces are dry, sand them smooth.
5. Paint your piece for a finished look.

Priming and painting the bookshelf creates a barrier against humidity and extends the bookshelf’s lifespan. 

Advantages of This Design

Creating your own bookshelf with stair treads leads to a durable, solid piece that you can customize to fit your space. You can complete the project with simple tools for a finished product that’s polished and elegant.