Among the common types of residential foundations, pier and beam are usually much less expensive to repair. This is primarily due to easier access with equipment and personnel. However, costs can increase in the event of severely damaged beams which need to be replaced and also the cost of repair of any water leaks.
Pier and beam foundations
Pier and beam foundations, as the name implies, are concrete footings and piers which support wood beams and floor joists. These foundations frequently have crawl spaces underneath the home.
Basements are usually constructed in northern climates where freeze/thaw environment occur and the footing depth must expand beneath the frost line—frequently four or more feet below the surface. In many of these situations, contractors will go ahead and dig for a basement and build basement walls that ensure the support for the home. The substructure of the basement is often below the depth over which the majority of the soil’s minimize or enlarge due to climate occurs. However, basements can suffer basement floor heave and lateral wall movement..
Deep foundations reach depths that are not normally deviant by seasonal environmental changes and are considered to be out of the zone of influence.
There are a many of other types of both shallow and deep foundations.
Quality foundation repair systems include pressed steel piers, helical piers, pressed concrete pilings, and drilled or poured concrete piers. The steel pier, also called a steel piling, is consistently the deepest driven pier providing the most foundation support. In addition to piers, drainage correction systems including surface drains, and French drains can also be provided to correct problem areas.
Quality foundation repair solutions are situation dependent, based upon the age and style of foundation and house as well as the soil conditions and goals of the property owner. Our opinion is that the steel pier is the best, as far as long lasting foundation support with minimal impact on vegetation. Our robust steel pier is driven to solid rock or a hard load bearing strata at pressures of up to 6,000 PSI, and depths of as much as 80 feet.
Time for foundation repair is typically 1 to 3 days. The amount of repair time is dependent upon the depth to which the pier system must be driven. The depth to which the pier system penetrates to rock or rock-like strata is not normally limited by soil moisture or soil density.
Steel piers are driven to bedrock or very hard load bearing strata.
Bracket Material is steel, typically ASTM A-36
No Shims, No Pins, and No Concrete
Typical 60″ pier section lengths, fewest connectors
Piershaft material is high carbon 2 7/8″ O.D., steel
Shaft sections have a typical yield strength of 50 KSI
All joints include a steel overlap of approximately 6″.
Piersindividually driven to rock or hard, rock like load bearing strata.
Friction reduction collar used to assure maximum depth.
HELICAL STEEL PIERS
Helical steel piers are another system used for home foundation leveling. Bracket material is the same as for steel piers. The first shaft section has one or more helical plates. Each section of steel is augured into the ground using a rotary hydraulic drive system. Extensions of steel pipe are typically 60″ long.
Helical piers are typically driven to a pre-set load level to provide adequate depth to get below the zone of seasonal moisture variation. The rotary helical pier system’s main advantage is that during installation no load is placed on the foundation, which makes it ideal for interior foundation repair. Helical piers will not normally achieve the depth of straight shaft pressed steel pilings.
Pressed Concrete Pilings provide a fast, relatively clean solution when compared with drilled piers. The system consists of pressed concrete pilings topped with a pier cap, concrete spacer, and steel shims.
The pressed concrete piling system requires a lot of lawn disruption when compared with steel piers. Typically, the hole required for this type of piling is twice that of a steel pier.
The pilings are hydraulically driven to refusal using an installation force of up to 5000 PSI. Studies have shown that due to the soil mechanics of friction and compression, this system will attain support strength of twice its installation force within one month after pier installation. The system consists of pressed concrete pilings topped with a pier cap, blocks and shims.
Other systems used in foundation repairs:
Drilled or Poured Concrete Piers: Holes are drilled to a depth of 9-12 feet below the surface, and then filled with reinforcing steel and concrete. The pier shown is commonly called a double 8, that is, twin 8 inch columns. Angular spacing of the two legs is typically 5-15 degrees. After allowing 4-7 days for the concrete to cure, thePoured concrete pier is topped with concrete spacers and shims as the house is leveled. This system may be used instead of steel piers when leveling the perimeter of pier and beam homes.
The pier system used under the interior of a pier and beam home may be as simple as re-shimming existing posts, or block and pad systems. Sometimes new poured concrete piers are installed on the surface of the ground. Steel shims are placed at the top of the pier to adjust the house level.
Mud Jacking is commonly used for driveways and sidewalks, and is less often used in concrete foundation repair. Mud jacking seldom provides satisfactory, long term correction to foundation problems, since the process doesn’t reach down to the zone of seasonal soil stability or bedrock. In Texas, the seasonal zone of soil stability is normally considered to be at a depth of 10-12 feet below the surface. At this depth, the soil moisture content remains relatively constant all year long.
Mud jacking doesn’t address the foundation problems that arise from inadequate soil compaction. Most foundation companies will not provide a long term warranty for a foundation repair using mud jacking.
Spread Footings were used in the past for slab foundation repairs, and have been proven to be less than satisfactory. The footing is typically installed directly under the beam as a poured concrete slab measuring 3′x3′x3′. Practice has shown that since the footing is in the highly expansive 3-5 foot soil depth, it may contribute to foundation upheaval and further foundation problems.
It’s interesting to note that in today’s world of residential construction, almost all homes are built on slab foundations. This is primarily because the builder finds them cheaper and faster to install. However, it is also important to note that many custom home builders are building on pier and beam foundations because of the flexibility in design. The finished product, with solid wood floors is another desirable feature many builders and homeowners appreciate.
Related: Average Cost of Foundation Repair