How to Build a Back Door Stoop

Install metal flashing onto the exterior wall section just under the door to protect the wall from the concrete step. Cut a section that extends from the bottom of the door to 4 inches beyond the start of the foundation in height and 10 inches beyond both sides of the door. Use tin snips to cut the flashing and screw the flashing in place with 1-inch galvanized wood screws.

Build up the soil at the base of the doorway to 6 inches in depth. Flatten the pile with a compactor or a pole tamper until the soil is as wide as the doorway and at least 36 inches deep.

Cover the tamped soil with 4 to 8 inches of gravel, depending on the height of your stoop, and tamp the gravel into place. Place several sections of rebar over the gravel before you pour the concrete and hold them in place with rebar chairs.

Build a wooden form around the compacted soil and gravel to hold the concrete. Use two sheets of plywood as high as the doorway, or at least within 4 inches, for the outer sides. Measure the length of the plywood sides by adding the length of the stoop plus 10 inches for each additional step. Hold them in place with wooden stakes and 2-by-4 supports screwed across the outside.

Form the stoop steps by screwing an 8-inch-wide plank upright and horizontally across the front of the wooden form and even with the ground. Place another plank 8 inches higher and 10 inches closer to the house. Repeat for any other steps until the last plank is even with the top of the stoop form. Leave the tops of the steps open for pouring in the concrete.

Mix concrete rated for 4200 psi or higher with enough water to form a thick, pudding-like texture. Use a wheelbarrow and a hoe to mix the concrete until no dry powder remains.

Shovel the wet concrete into the bottom step and use a trowel to pack it into the corners of the wooden form. Use a wooden board across the top of the step to smooth the concrete evenly.

Add concrete to the next step and repeat the packing and smoothing process. Mix up more concrete if necessary and fill in the top of the stoop. Use the wooden board to smooth off the top, dragging it back and forth to push the concrete in place. Tap the sides of the wooden form to release any air pockets.

Allow the concrete to dry for about 30 minutes then remove the wooden form. Use a rubber float to smooth the edges of the steps and the sides of the stoop, adding more fresh concrete as needed. Drag a flat broom across the surface of the steps to form a slight raised surface for traction.

Cure the steps for at least 48 hours before stepping lightly on them and a week before resuming normal foot traffic.