How to Build a DIY Sandbox

Tools and Materials

Note

Product costs, availability and item numbers may vary online or by market.

Planning Your DIY Sandbox

Pick a location with enough space for the finished sandbox: the below 8-foot-by-8-foot frame takes up 64 square feet. If you can't spare the space, build a smaller sandbox in the area that you have. The plans are easy to modify as needed.

Sun or Shade?

A sunny spot keeps the sandbox bright, but it can also mean hot sand and UV exposure. Under a tree offers natural shade, yet falling leaves and debris can become an issue. The best choice is a location that fits your yard and gets some shade from your home or a nearby structure.

When choosing the size of your sandbox, consider including extra room for toys and your child’s playmates too. Think about how much sand you’ll need. The below build requires 32 cubic feet of sand (about sixty-four 50-pound bags), however you can easily reduce the dimensions. The bracing and corner assembly construction will be the same regardless of the length and width.

What Kind of Wood Should I Use?

What Kind of Wood?

For a sandbox, the best wood options are those that are durable, weather-resistant, and safe for children. Here are some good choices:

Pressure-Treated Lumber

Affordable and widely available.
Treated to resist rot and insects.
Labeled for residential use and ground contact.

Cedar

Naturally rot-resistant and insect-repellent.
Smooth and splinter-resistant.
Attractive, but more expensive than treated lumber.

Redwood

Excellent durability and weather resistance.
Beautiful finish, but pricey and less common.

Composite Deck Boards

Splinter-free and long-lasting.
Requires less maintenance.
Higher cost but great for longevity.

Tip

It is best to avoid untreated pine or hardwood boards that can rot quickly outdoors.

Preparing the Sandbox Site

Once you’ve decided on your sandbox’s location and size, you can measure, mark and prepare the area. Use mason line string and landscape stakes to mark the layout of the sandbox.

Cut out the shape with a shovel and remove the sod. Dig out the soil about four inches deep. You’ll want the bottom edge of the sandbox slightly below the surface to keep the walls in place. Level out the area and put down a layer of landscape fabric. Use landscape staples to hold the fabric in place. This allows drainage and prevents weeds and grass from popping up through the sand.

Assembling the Sandbox

To reduce the amount of cutting, our sandbox is designed to use pre-cut 8-foot lumber.

Constructing the Base

Aim for a play area depth of about 11 inches. To build the base, position two 2-inch by 8-inch boards on edge so one end overlaps the other. Secure them with 3-inch deck screws to create a corner. Repeat for the remaining corners to form the base frame. Check that each corner is square and the entire base sits level before moving on.

Add the Second Layer

Wipe down the top edges of the boards with a cloth to remove dirt and debris. Apply a bead of construction adhesive along the edge of one board, then press an 8-foot board edge-to-edge on top of it. Tip: Choose an adhesive with instant hold yet enough working time before it sets and follow the manufacturer’s curing instructions.

As with the base layer, overlap the board ends at the corners and secure them with 3-inch deck screws. Take your time to align the edges for a smooth surface on both sides. Repeat this process to complete the second layer.

Add Corner Braces for Stability

Adding corner braces to your sandbox frame is a simple way to boost stability and prevent shifting over time. Metal corner brackets or heavy-duty steel angle braces reinforce the joints where boards meet, keeping the frame square and secure even with active play. Install them on the inside corners using exterior-grade screws for long-lasting strength.

Completing Your Sandbox

Add Seating

Adding seating in the corners is easy and will add both style and function. Here is a simple way to accomplish this touch.

Corner Seating:
Mark the center of a circular board with a pencil and straight edge, then rotate the board a quarter turn and mark the center again to create four equal sections. Cut along the lines with a circular saw to form four seats.

Position each seat so the 90° cut fits snugly into a sandbox corner. Secure with three deck screws on each side. Smooth the edges with a sanding block, then finish with exterior paint or a protective stain to guard against the elements and add a pop of color.

Be sure to wear a dust mask and eye protection when cutting or sanding lumber.

Landscaping

Landscaping around your sandbox adds both function and style. Consider creating a soft play zone around the frame with rubber mulch or pea gravel to prevent muddy spots and improve drainage. Low-maintenance plants can frame the area and keep grass from creeping in. For extra shade, add a small pergola or position potted plants nearby, just make sure they’re non-toxic and safe for kids.

How Much Sand Do You Need for a DIY Sandbox?

To calculate the amount of sandbox sand, multiply the sandbox’s length by its width, then multiply by its height to get the volume in cubic feet. For example, an 8-foot by 8-foot by 1-foot sandbox equals 64 cubic feet. Play sand—typically prewashed river sand—is smooth, clean, and sold in 50-pound bags, each covering about ½ cubic foot. Since you don’t need to fill the box to the top, about 64 bags will fill an 8 x 8 sandbox halfway, creating the perfect depth for safe, fun play.

Keep Your Sandbox Clean and Protected

Covering your sandbox when it’s not in use helps keep the sand clean, dry, and free from animals. A simple plastic tarp makes an affordable, quick cover. For better drainage, place a 5-gallon bucket upside down in the center before securing the tarp—this creates a peak so water runs off instead of pooling.

For a more permanent option, attach wood or plastic lattice, metal screen, hardware cloth, or chicken wire to a wooden frame. These covers block leaves and debris but won’t keep out rain, so pair them with a tarp for full protection.

Creating a DIY sandbox is an easy way to give your child a fun outdoor play area. Choose a level spot in your yard and build a sturdy frame using pressure-treated boards. A homemade sandbox is a budget-friendly project that turns any backyard into a kid-friendly space for hours of play.