Helical pile installers in Missouri

Helical Piles in Missouri

Missouri is one of the country's major karst states. The Missouri Department of Natural Resources has identified about 16,000 sinkholes, with many more undocumented, formed where groundwater dissolves limestone and dolomite. The southeast corner of the state also sits in the New Madrid Seismic Zone, the most active seismic area east of the Rockies.

Add clay soils that shrink and swell and winters cold enough to heave shallow footings, and many Missouri homeowners end up looking for deeper support. Helical piers install with compact equipment, can be tested by torque as they go in, and carry load right away, which makes them a common choice for foundation repair and additions. In older St. Louis and Kansas City neighborhoods, they are also used where brick homes sit close together and there is little room for excavation.

Common uses in Missouri

• Underpinning homes with settlement cracks or sloping floors
• Frost-depth footings for decks, porches, and sunrooms
• Additions and garages on existing lots
• Docks and shoreline structures at the Lake of the Ozarks and other reservoirs
• Ground-mount solar and agricultural buildings

Soil, frost depth, and code considerations

Missouri has no single statewide residential frost depth for site-built homes, so local codes apply. For manufactured home installations, the Missouri Public Service Commission's frost depth map ranges from 12 inches south of I-44 to 25 inches north of Highway 36, and notes that local jurisdictions may require more. Kansas City and St. Louis area codes commonly call for 30 to 36 inches, so confirm the number with your building department.

Helical pile products are typically evaluated by ICC-ES under AC358, and the local building department handles permits. In karst areas, an engineer may want borings or a site review before specifying piles, along with the target installation torque that verifies each pier's capacity. The Missouri Geological Survey can help property owners determine whether a collapse is related to a natural sinkhole, which is useful information before choosing a repair.

Typical helical pier costs in Missouri

National pricing from HomeGuide places installed helical piers around $2,000 to $4,000 apiece, with about $3,000 common. Missouri costs vary with depth to bearing, pier count, and access around the house. Read more in our helical pier cost guide.

Find a helical pile installer in Missouri

Below are installers, foundation repair companies, manufacturers, and distributors that serve Missouri. Contractors cover the Kansas City and St. Louis metros as well as Springfield and Columbia. If your property is in sinkhole country, ask whether the contractor has worked with engineers on karst sites and how they respond if a pile hits a void during installation.

Missouri helical pile FAQs

Can helical piers be used near sinkholes in Missouri?

Sometimes, with engineering review. Helical piers can reach past loose soil, but karst voids are irregular. A site investigation helps determine whether piles, grouting, or another approach is appropriate.

How deep do helical piles go in Missouri?

They must extend below the local frost line, often 30 to 36 inches in the big metros, and then deep enough to reach the target torque. Clay profiles and bedrock depth vary widely across the state.

Do I need a permit for helical piers in Missouri?

Cities and many counties require permits for foundation repair, decks, and additions, but some rural counties have limited building code enforcement. Check with your local office.