Different Ways to Build a Porch Foundation

Building to Scale

• A drawing of your home to scale is important. The porch must look original to the home's construction. As you face a house, the curbside view of a porch is critical to market appeal. The spacing of columns under a porch deck or the color of the porch foundation, if enclosed, will come into play. Create a reproduction of your home on graph paper for a back porch or side porch, too.

Match House Foundation

• Enclosing a porch foundation will require footings and enclosure materials that match the home's existing foundation. Picture building this type of porch foundation as constructing a short concrete block wall that will be covered with stone or brick. The porch flooring will rest on this bottom box-shaped enclosure. As another option, you can apply stucco over concrete blocks on the porch foundation. While you can select wood products to enclose a porch foundation, keep in mind that wood will likely need replacing within a few years.

Raised Wooden Porch

• An open porch foundation requires masonry or wood columns. These columns will rest on small concrete slabs. You will need to pour concrete sections that are 12 inches square and 12 inches deep, for example, for the support columns holding up the porch to rest on. The porch structure typically will be made of wood. This design is perfect for some porches, such as a back porch holding a hot tub, because you may need to crawl under the porch to access pipes or drains.

Poured Concrete Foundation

• A simple concrete slab is another alternative. Pouring a foundation to support the weight of roofing and porch furnishings requires metal gridwork inside the concrete. An 18-inch deep slab will support the weight of almost any porch roofing weight. For a porch deck only, with no roofing, you can pour a 10-inch floor. You can cover this slab with brick or pavers for a more decorative look.

Filler Material Options

• A taller porch will require using concrete, dirt and gravel filler. For example, if you need a porch 8-feet tall on the front of a single-story brick house, you will need to construct concrete footings for foundational walls. You will cover this foundation on three sides with brick to match the home's brick. The porch base -- which is a deep 8-foot box -- will require filling with packed dirt and about 12 inches of gravel on top before you install a concrete floor as the main porch deck. You will need a "lip" of concrete to protrude out over the foundation walls about 8 inches so that water will shed properly.