How to Build Under-Sink Pull-Out Drawers

Vanity cabinets often become deep, dark voids where bottles and supplies vanish into the back corners. By installing a custom sliding drawer system, you transform that wasted vertical space into an organized, accessible utility zone. When done well, the drawers slide silently, clear the sink trap, and allow you to see exactly what you have without digging. The secret to success here is precision measurement. Because under-sink areas feature irregular plumbing pipes and floor-mounted supply lines, a one-size-fits-all kit rarely works. We are building custom-depth drawer boxes that sit on heavy-duty ball-bearing slides, designed to wrap around your specific plumbing layout. Expect to spend a morning on the build and an afternoon installing, but the gain in usable storage is permanent.

1. Map Your Plumbing First. Measure the interior width, depth, and height of your vanity. Mark the exact location of the sink drain pipe and supply lines on your floor plan to ensure the drawer box won't collide with them.
2. Build Square Boxes. Cut 1/2-inch birch plywood to size for the sides, front, and back. Assemble the boxes using wood glue and brad nails, ensuring the frame is perfectly square.
3. Seal the Bottom. Attach the 1/4-inch plywood bottom to the underside of your frame. Use wood glue along the edges and secure with staples or finish nails every 4 inches.
4. Level the Slides. Screw the stationary side of the ball-bearing slides into the cabinet walls. Use a spacer block to ensure they are perfectly level and set back the required distance from the door face.
5. Align Drawer Members. Secure the matching slide members to the sides of your drawer boxes. Align them precisely with the slides already mounted in the cabinet.
6. Smooth the Glide. Slide the drawers into the tracks and check for binding. Adjust the mounting screws in the slots if the drawer pulls unevenly or scrapes the cabinet floor.