Concrete Formwork Techniques

Basic Form

• 1

  Measure and mark the work area. Place a wooden stake at each corner and run string between the stakes to lay out the area.

• 2

  Cut 2-by-4-inch boards to the area's width and length. Use a circular saw for smooth, even cuts.

• 3

  Place the boards along the intended area. Sit the boards so they create a 4-inch-high frame around the work space. Place the ends so they're flush to each other, making a solid frame. Hold the frame in place with a wooden stake pounded into the ground on both sides and both ends of the boards.

Reinforced Concrete Form

• 4

  Lay out the basic frame around the area. Reinforced forms are typically for larger areas or for concrete that requires higher weight-bearing.

• 5

  Lay Rebar between the wood forms. Begin approximately 6 inches from the edge of the wood and lay the first rod. Measure 12 inches and lay another piece. Continue in this manner across the width of the basic frame.

• 6

  Pour the first layer of concrete into the form. This layer should cover the rebar.

• 7

  Lay welded mesh wire into the wet layer of concrete. Begin at one end of the form and work in the same direction as the concrete is being poured. Let the mesh sink into the concrete until it's below the surface. Pour the second layer of concrete.

Walls

• 8

  Create a footer for the wall. Use the basic form technique to create the base for the wall. Pour the concrete and allow it to dry.

• 9

  Cut 2-by-4-inch boards to the height of the wall. Cut one for each foot of the wall's length, not exceeding 6 feet.

• 10

  Lay out the boards on a flat surface -- width side-down and 1 foot apart -- and attach a top and bottom frame of 2-by-4-inch boards. Use 4-inch nails to attach the top and bottom boards to each piece.

• 11

  Cut 3/4-inch plywood to fit the frame. Nail it to the frame on one side so the entire side is covered, top to bottom.

• 12

  Turn the frame so the plywood is flat to the ground. Measure a foot from the bottom of the frame and nail a 1-by-2-inch board in place horizontally completely across the frame. Nail at the bottom edge of the board. Measure up another 2 inches and place a second 1-by-2-inch board. Nail at the top edge of this board. Repeat this action up the frame until you're 1 foot from the top. These are known as walers and will hold the wire ties in place.

• 13

  Slide wire ties through the opening between and behind the walers every 3 feet. This wire will connect to the second frame.

• 14

  Repeat the process to create a second, identical form.

• 15

  Place the forms on either side of the poured and dry concrete footer. Attach the wire ties to the opposite side.

• 16

  Create and attach the end sheaths. Cut 3/4-inch plywood to the width of the intended wall. Nail the boards to each end of the forms to completely enclose the frame. You're ready to pour the concrete.