Pier and Beam Foundation: Designs, Costs, and Building Tips


Every home is built on a foundation, but a great home in particular is built on a great foundation. With a myriad of choices available out there, choosing the right foundation is key to ensuring that you have a home that actually lasts. 

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One such choice is the pier and beam foundation, a foundation style that has been gaining popularity among newer homes. Its raised style gives it a set of characteristics that not only set it apart from other approaches, but also provide some unique benefits in certain cases.

But how exactly does it work? What should I expect when I choose a pier and beam foundation for my home? And it is actually any good?

Learn more about the pier and beam foundation in this guide to find out whether this design is right for your project. 

What Is a Pier and Beam Foundation?

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A pier and beam foundation is one of the three primary types of permanent foundations used in homes, the other two being the slab foundation and the basement foundation. 

As the name suggests, a pier and beam foundation (also called “pier and grade beam”) is made up of vertical pillars or piers made of concrete, brick, or stone driven into the ground, on which are mounted wooden beams that support the house above.

Like the other two types, pier and beam foundations are all good options from a general standpoint; but as we will go into detail later, each foundation type has its advantages and disadvantages that make them better for some homes over others. For instance, homes built in storm-prone areas are one of the most common and popular applications for pier and beam foundations.

Advantages of Pier and Beam Foundations

Flood resistance. Building your home on a pier and beam foundation will place your home at a higher elevation compared to a slab or a basement setup, which gives you valuable leeway to protect your home from most floods.

Usable crawl space. With the home raised up above the ground, the pier and beam foundation creates a crawl space under the home that could be appropriated for various uses—say, for example, routing electrics, plumbing, and HVAC.

Aesthetic boost. The added elevation of a home with a pier and beam foundation also has its aesthetic appeal, making the house look taller and larger while also allowing for the construction of a raised front porch area that itself opens up a new range of design and decor options.

Common Problems With Pier And Beam Foundations

Potential pest & mold problems. Damp and dark are the two main ingredients for a potential new rooting ground for mold & mildew, as well as a new home for rats, racoons, and other critters; and these ingredients are built right into every crawl space if they aren’t given the right treatments.

Creaky floors. While they do their jobs perfectly well, pier and beam foundations don’t quite have the same level of support as the actual ground. The mostly hollow crawl space under your home could, therefore, cause your floors to creak. A change of flooring usually solves this, however.

Wind drafts. Winds can and do pass into a typical crawl space and up into the home, making it draftier and less energy efficient. Treating your crawl space as an extension of your home and giving it the same insulation treatment will greatly mitigate this problem. 

How Much Does Pier and Beam Foundation Cost

Like all home foundations, the cost of a pier and beam foundation greatly depends on how large your home is. Generally speaking, however, a pier and beam foundation will usually cost around $4 to $8 per square foot depending on the level of quality one wants from said foundation.

As you can probably imagine, most of this price really goes into the cost of materials and labor, which is understandable considering the more labor-intensive nature of building a pier and beam foundation. 

Besides the actual foundation itself, one also has to pay very close attention to the crawl space created after building the pier and beam structure. To avoid certain issues (that we touched on in the previous section), one can resolve to have insulation, vapor barriers, and other creature comforts in the crawl space at extra cost.

The added cost of construction, surprisingly enough, actually contributes to a lower cost of repair and maintenance compared to slab and basement foundations. The main reason for this is that most of the main supporting structure are already buried deep underground, leaving only the wooden support beams to be the main point of maintenance.

Pier and Beam Foundation Designs

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The above example is what could be considered as the “basic” form of a pier and beam foundation, with low wooden beams mounted on and supported by concrete piers that are usually built to high standards, being the parts that are the most difficult to access.

Source: designingbuildings.co.uk

This second design makes use of round concrete pillars as the piers of the home, raising it up a lot higher than the previous example. The increased height gives easier access to the crawl space inside at the cost of needing more and better sealing to avoid draftiness.

Source: csfoundations.com

This third and last example has a bit of a different approach to their pier and beam foundation, with metal beams supporting the house’s wood frame in a crawlspace made with pretty extensive treatment. Such treatment is arguably a requirement for less maintenance in the crawl space in the future.

How to Build Pier And Beam Foundation

Step 1: Leveling

Before any material goes into the building site, the location and set up of your pier and beam foundation is established and finalised here. Said leveling is important for pier and beam foundations because of its many individual piers.

Any deviations can cause serious problems for the home down the line; as such, leveling must be done as accurately as possible.

Step 2: Digging

With the plans laid out, the next step is, of course, to dig out the holes where the piers are meant to go. The depth of these holes can vary quite a bit depending on the condition of the earth on the building site. 

For additional support, however, one can opt to have a concrete slab poured into the foundation at a lower depth to serve as the piers’ anchor. Although the added complexity contributes to more cost, the result is a much more stable structure in some cases.

Step 3: Filling

With the holes for the piers all dug up, forms are placed into the holes into which concrete is filled to create the namesake piers of the foundation. As noted earlier, leveling is very important for pier and beam foundations, so the forms and the poured concrete are kept level during this process.

Mounting hardware for the beams are then installed before the concrete cures to ensure maximum bonding strength. The most common of these is a simple metal bracket that holds wooden beams with bolts and screws, although other styles also exist that serve slightly different purposes.

Step 4: Mounting

Once the concrete piers have cured, the wooden beams are mounted to the metal brackets noted earlier, then the wooden subfloor frame is placed and mounted on top of that. And with that, the pier and beam foundation is complete.