How to Make Molds for Concrete Window Wells

Measuring and Cutting

• 1

  Measure the window to determine the size of window well you want. Window well depth depends on the size and depth of the window. For instance, if you install a 12-inch tall window 6 inches below ground level, you need an 18-inch tall window well. The width of the well also depends on the window, while depth depends on personal preference.

• 2

  Draw the well, using a paper and pencil. Include the dimensions for the inside rim of the well and the outside rim, as well as the thickness of the well. A thickness of 6 inches should suffice for a window well.

• 3

  Put on work boots and work gloves.

• 4

  Cut all of the plywood boards to the desired height for the window well, using a circular saw. In the example, the height is 18 inches. Measure the height with a tape measure and mark the boards with a pencil.

• 5

  Saw two plywood boards to a width equal to that of the desired width of the inside rim of the window well, using a circular saw. Write the words “inside rim sides” on these boards with a pencil.

• 6

  Cut two plywood boards to a width equal to that of the desired width of the outside rim of the window well, using a circular saw. Write the words “outside rim sides” on these boards with a pencil.

• 7

  Rip one plywood board to a width equal to that of the desired width of the inside rim of the window well, using a circular saw. Write the words “inside rim back” on the board.

• 8

  Cut one plywood board to a width equal to that of the desired width of the outside rim of the window well, using a circular saw. Write the words “outside rim back” on the board.

• 9

  Saw the 2-by-10s so two of them equal the width of the "inside rim side" boards and one of them equals the width of the "inside rim back board." Use the circular saw.

• 10

  Measure a 45 degree angle on one end of the 2-by10s for the sides of the well, using an angle measure. Mark the angle with a pencil.

• 11

  Measure 45 degree angles at both ends of the 2-by-10 cut to the length of the back of the well, using an angle measure. Mark the angle with a pencil.

• 12

  Cut along the lines drawn on the ends of the 2-by-10s with a circular saw.

• 13

  Cut 24 2-by-4s to the height of the plywood boards, using a circular saw. All plywood boards should measure the same height, and differ in width.

• 14

  Cut 18 6-inch long pieces of wood from the remaining 2-by-4s, using the circular saw. Cut these pieces to a width of 1 to 3 inches.

Assembly

• 15

  Attach four 2-by-4s to one face of each of the 6 plywood boards, using a nail gun. Affix the 2-by-4s so they sit perpendicular to the boards, protruding away from them like spines. Space them at even intervals, based on the width of each board.

• 16

  Attach one 2-by-10 perpendicularly to the bottom of each board intended for the inside rim of the well, using a nail gun. Attach the 2-by-10s with angles cut in only one end to the "inside rim side" boards and the board with angles cut in each end to the "inside rim back" board.

• 17

  Arrange the pieces of the inside rim in a “U” shape. Face the boards toward one another, so the 2-by-4 spines and 2-by-10s all sit in the middle of the shape. Set up the boards so the angled ends of the 2-by-10s on the side boards fit with the angled ends on the back board.

• 18

  Affix the 6-inch long pieces of 2-by-4 to the backs of the boards arranged in a “U” shape, using the nail gun. Place six pieces on each board, in two rows of three. Space the rows evenly, based on the width of the board.

• 19

  Line up the board labeled “outside rim back” so it fits up against the 6-inch long pieces extending from the back of the board labeled “inside rim back." Drive nails through the board using the nailer so they attach to the 6-inch pieces extending from the other board.

• 20

  Repeat this process to attach the “outside rim side” boards to the “inside rim side” boards.

• 21

  Locate the seams where the outside rim boards meet, and where the inside rim boards meet. Drive nails through the boards every 6 inches along the height of the seam to seal the seam.

• 22

  Measure the distance from the spines protruding from the inside rim side boards into the middle of the “U” shape. Cut four 2-by-4s to a length equal to this distance.

• 23

  Place the 2-by-4s between the spines of the opposite side boards at the midpoint of the height of the board. Attach the 2-by-4s to the spines on either side of it using the nail gun. These boards provide support against the weight of the wet concrete, which pushes against the sides of the forms as it dries.

• 24

  Measure a line protruding from the midpoint of the height of the "inside rim back" board of the form with the tape measure. Extend this line down from the board at a 60 degree angle. Determine the angle using an angle measure.

• 25

  Cut four 2-by-4s to the length of the diagonal line measured, with a circular saw. Measure a 60 degree angle at each end of these boards with the angle measure and cut along the line with a circular saw.

• 26

  Attach these boards so they extend from the midpoint of the height of the back board to the ground, using a nailer. You should be finished building a “U” shaped mold for a concrete window well. When ready, pour concrete into the mold to create the window well.