PIER AND BEAM FOUNDATION
Pier and beam foundations usually date to before the 1960s. During this time, advances in concrete pouring hadn’t allowed for slab foundations, and so pier and beam foundations were the most solid and durable foundation type available. Pier and beam foundations raise the house above the ground level, often allowing for a crawl space or basement.
Their unique construction style, combined with their age, means that many pier and beam foundations require regular inspection. However, that doesn’t mean that a pier and beam foundation won’t be a reliable and enduring foundation for your home.
For information on other kinds of foundation styles, see our page on Types of Home Foundation.
This guide will walk you through the different aspects of a pier and beam foundation, from costs, pros and cons, to potential problem areas. While it’s unlikely that you chose your pier and beam foundation, it does have some advantages over a concrete slab foundation – advantages we’ll go over in this guide.
CONSTRUCTION METHOD
Before the development of modern concrete pouring, the best way to give a home a solid platform was to use a pier and beam system. To construct a pier and beam foundation involves the following steps:
1
Sink pier
Sink a wooden pier – usually cedar – into the ground until it hits solid rock.
2
Add base
Add a concrete base to the pier to prevent it from moving.
3
Add beams
Extend beams from each pier, connecting to the joists of the home.
4
Set floor
Rest the floor on this system.
Usually, pier and beam systems leave a crawl space of about 18 inches below the home. In this space, you place the plumbing system and the electrical panel of the home.
This is a relatively simple way of building a sturdy home, and until it became surpassed by concrete pouring, it was the standard for home building throughout much of the United States.
COSTS
Generally, you can expect to pay around $9 per square foot to have a pier and beam system installed. This price may be higher depending on where you live in the United States, as pier and beam has become something of a niche request. For an average size home, you will pay between $7,200 and $13,500.
If you have a pier and beam foundation that needs repairing, it can be expensive. To install a hydraulic pier to lift the home, you will pay around $1,340. The average home needs between 8 and 10 piers when it requires repairing, giving you a final bill of between $10,720 and $13,400.
For more information on the costs of different types of foundations, see our page on Average Cost of Home Foundation.
PROS OF PIER AND BEAM
Despite the costs involved in the repair, many people believe pier and beam systems to be preferable to concrete slab foundations.
Below are the advantages that a pier and beam foundation has over foundation types such as a concrete slab foundation or a monolithic slab foundation.
EASE OF ACCESS
The big advantage is that a pier and beam system leads to space underneath your home. The structure is raised from the ground allowing either a crawl space or a basement.
If you have electrical or plumbing issues, it’s easy to access the wires or pipes in order to repair them.
TEMPERATURE CONTROL
Having space underneath your home makes it easier to control the temperature. If you live in a hot climate, the ventilation under your house will help keep everything cooler.
If you live in a cooler climate, you can insulate the space, which will save on heating costs and keep your home warm even in the depths of winter.
MODULAR
Because of the design of a pier and beam home, most problems are localized to individual piers or beams. This makes it easier to repair a single part of the foundation, rather than the entirety of the space.
RELOCATION
In some cases, you can relocate a pier and beam house by lifting it up and loading it onto a specially-designed truck. This is not possible with a concrete slab foundation.
CONS OF PIER AND BEAM
Although there are positives to a pier and beam foundation, there are, of course, downsides.
The primary one is that many tend to be older, and therefore more in need of repair. However, this isn’t a fault of the design style per se, more that it is no longer a method of choice for many contractors.
Instead, the structural faults are:
MOISTURE
The space underneath a pier and beam home can be a curse as well as a blessing. It can very quickly fill with moisture and, since it’s rarely a space you use, you won’t always notice if it becomes damp.
Unchecked, this moisture can lead to damage to the structure, or to mold developing.
PESTS
Again, the space at the bottom of your home can become its own home to pests, particularly rodents and bugs. These can then spread throughout the rest of your house. If this happens, you’ll need to call in an exterminator to rid you of the problem.
FREEZING
If the weather drops below freezing, any moisture that has accumulated under your home will freeze, and this can cause major damage. Sometimes, even insulation can become saturated with water, and this will freeze too.
WHEN PIER AND BEAM IS THE
BEST OPTION
Pier and beam foundations are best suited to a unique set of circumstances. There are three particular situations in which they are a good option.
When pier and beam should be a consideration:
- In locations where the soil regularly expands and contracts. Pier and beam foundations are much more flexible in this respect than concrete slab foundations.
- On building sites where the land is uneven. Because you can adjust the height of the piers and beams, you can create an even platform despite the land being sloped or uneven underneath.
- Where there is potential for flooding. If there is potential for flooding, then the home may need to be raised further off of the ground. You can also adjust the height of the home using a pier and beam to give yourself space in case of flooding.
In general, therefore, if you are building a home that is not suited to a concrete pour, then the next best option for you may be a pier and beam. Despite this, some contractors prefer to regrade and level the land and then pour concrete, rather than installing a pier and beam system.
POTENTIAL PROBLEMS
Because of the unique construction style of pier and beam foundations – coupled with the relative age of many of this type of design – there are common problems that emerge.
If you have a pier and beam foundation in your home, then it is likely that you will need to undertake regular inspections of the structure in order to catch issues before they become too problematic and expensive for you to fix.
The most common problems are:
UNDERLYING SOIL
Over time, the moisture levels of the soil can cause cracks in the foundation. The most common type of soil to do this is soil that contains high levels of clay. Clay soil can retain a larger volume of water than other soil types. Excess moisture causes the soil to expand, and the resulting hydrostatic pressure places pressure on the foundation.
Signs of this include the following:
IMPROPER DRAINAGE
A related feature is improper drainage. If water does not drain properly from the basement, then it can place major stresses on the foundation from the inside. If water remains in the basement it will gradually seep down and reach the foundation layers.
If your basement is constantly wet, it also prevents the foundation from drying – exacerbating the problem of excess moisture in the underlying soil.
SUBSIDING
Many pier and beam foundation structures were built using cedar. While this does make them robust and flexible, it also means that they have a limited footing area. This limited area effectively increases the pressure on other parts of the foundation.
This means that, over time, the instability of the soil will cause the piers to begin to sink into the ground. Almost every type of pier and beam foundation experiences some level of subsiding, only getting worse over time. The older the foundation, the more likely it will have sunk and may require shoring up.
While a pier and beam system may not be one you’d choose if you were to be building your home from scratch, it is a durable type of foundation that can last for many years. That said, you will need to make extra sure you inspect and address any small issues, as once this type of foundation starts to break down, it ages very quickly.
Pier and beam have some advantages over modern foundations – namely the access to space. Being able to access plumbing or central heating systems, for example, means that maintenance and repair are far easier. So, while you may not have chosen your pier and beam foundation, it doesn’t mean that you don’t have a robust (and potentially advantageous) foundation that will last you many years.