Building a Wooden Form for Concrete Footings
A footer, a concrete base beneath a building, supports basement floors and walls in residential projects. It is placed under the frost line to keep the foundation stable despite freezing and thawing. To cast a footer, you first need to construct a wooden form that holds the concrete while it sets.
By Taylor Evans4 steps
Concrete footers support the foundation of a building.
In construction, a footer serves as a concrete base that supports a building. For residential buildings, footers carry the weight of the basement floor and walls. The footer is buried below the frost line, which prevents the foundation from being affected by ground movement caused by freezing and thawing. Before pouring concrete into the footer, you need to build a wooden frame that will hold the concrete as it hardens.
Step 1
Determine and mark where the foundation walls will go. Use spray paint to draw two lines that indicate the inner and outer boundaries of the walls. The footer's thickness should be no less than double that of the wall.
Step 2
Dig a trench between the two lines, making sure it reaches below the frost line. Check with your local zoning board to find the required depth for your area -- in the southern United States, it might be just a few inches, while in the northern United States, it could be up to 5 feet. The depth and length of the footer will determine whether you can dig by hand with a shovel or need to rent a 1 1/2-ton excavator.
Step 3
Place wooden stakes into the ground within the trench. Set them a few inches inside the trench walls, spacing them every three feet.
Step 4
Attach two-by-four boards to the inside edges of the stakes using nails. Along the entire length of the footer, stack two boards on their side edges, with the bottom board's side edge resting directly on the ground. When choosing lumber for the footer frame, pick the straightest two-by-fours available.
