How to Build a Waterbed Foundation

Cut Foundation Frame Pieces

• 1

  Use a tape measure to measure and cut two pieces of 2-by-10-inch lumber 86 inches long on a table saw to form the left and right sides of the frame. Cut two pieces of 2-by-10 lumber 60 inches long to form the top and bottom pieces for the foundation.

• 2

  Place the wood pieces for the left and right sides to frame the foundation and the top and bottom in position in the area where the bed will be located.

• 3

  Butt the far left edge of the top piece to the inner edge of the left side piece. Center the hinge piece in between the two pieces. Use a carpenter’s pencil to fill in the screw holes.

• 4

  Drill starter pilot holes, following your fill-in guides. Do not drill down all the way. Just go far enough to create a pre-drilled starter hole. You will finish attaching the screws manually.

• 5

  Repeat steps 3 and 4 with the pieces for the right and bottom pieces for the bed frame.

Attach Foundation Frame Pieces

• 6

  Line all pieces in position for the top, bottom, left and right sides for the foundation.

• 7

  Attach and tighten C-clamps to hold the corners of the pieces together at 90-degree angles.

• 8

  Tighten screws to connect the upper left corners, and use the same method to connect the lower right corners, upper right corners and and lower right corners. Tighten all screws to complete connecting each piece.

Make the Foundation Platform to Support the Waterbed Mattress

• 9

  Cut 2 plywood boards to form the foundation platform piece to hold and support the waterbed mattress. Each board should measure 86 inches long and 33 inches wide. The platform for the mattress will hang over the frame 3 inches on each side to accommodate the natural shifting of the waterbed mattress.

• 10

  Mark the boards with a carpenter's pencil so you can identify their position for placement on the frame. Use a marking that is easy to remember, such as “BL” for the board that will be on the left and “BR” for the board on the right.

• 11

  Use a carpenter’s pencil to make guide marks for screw holes. Measure 1½ inches from the right and left edges. Measure 7½ inches from these points and make additional marks on all edges (upper, lower, left and right). These holes will be used to secure the top panels to support the mattress.

Attach Mattress Platform Boards

• 12

  Place the board for the left side on top of the frame. Place the board for the right side on top of the frame.

• 13

  Center each board so it lines up with your center marks for the top and bottom pieces for the frame.

• 14

  Insert screws to attach the platform boards to the frame to complete your waterbed frame building project.