When Insta-Footing Can Support an Indoor Column

Insta-Footing may support an interior post or column when the design load, plate size, existing slab, supporting material, anchorage, connector and other project conditions meet Nolan’s current documents.

Governing documents

• Governing Insta-Footing design report
• Current Insta-Footing installation instructions

When is Insta-Footing the relevant product?

Insta-Footing is relevant where a design calls for an interior supporting post or column and the load can be distributed through a qualifying existing concrete slab.

The product sits flat on top of the slab. The specified post is centered on the steel plate and secured through the connector detail. The selected anchorage holds the plate in position while the post load bears concentrically through the plate into the slab and compacted support below.

The documented application limits require:

• Installation on a qualifying existing concrete slab, not directly on soil.
• A level slab in fair or better condition, without cracks, deterioration, settlement, voids, moisture damage, or another condition that may affect capacity.
• Verified slab thickness, concrete strength, and tight compacted support below.
• An interior supporting post or column application covered by the design.
• Design and connector details for any post or load configuration outside the report’s analyzed pairings.

Which plate and post configurations were analyzed?

The current Insta-Footing design report, Revision 1 – Code Update, analyzes these configurations. Nolan’s current instructions use the same pairings:

Plate Size	Standard Analyzed Post	Limiting Capacity
12 × 12 inches	Nominal 4 × 4	9,150 pounds
16 × 16 inches	Nominal 6 × 6	12,700 pounds

Concrete bending governs both limiting capacities.

These analyzed pairings do not prohibit a properly designed 4 × 6 or steel-post application. A 4 × 6, steel, or other post configuration requires connector and design details establishing the load path, attachment, compatibility, and allowable project load.

The allowable project load may be lower. Confirm the required post reaction from the design before selecting the plate. Do not estimate it from the room size, beam appearance, post height, or the weight of one object above.

What slab conditions are required?

Before installation, verify all of the following:

• The slab is level.
• The slab is sound and in fair or better condition.
• The slab is at least 3½ inches thick.
• The concrete has minimum compressive strength of 2,500 psi.
• Compacted soil or stone remains in tight contact beneath the slab.
• The supporting material provides at least 2,000 psf allowable bearing.
• The plate can be located at least 7 inches from every slab edge.
• Additional anchor-manufacturer clearances can be maintained.
• Embedded utilities are identified before drilling.

Stop if the slab has cracking, deterioration, settlement, voids, moisture damage, an uneven bearing surface, or another condition that may affect capacity.

A larger plate does not cure an unverified slab.

If existing conditions require leveling, Nolan’s current product page for the 12 × 12 plate and current product page for the 16 × 16 plate allow non-shrink grout. Use grout only under an approved leveling detail; it does not replace the required slab thickness, concrete strength, bearing support, full plate contact, or other governing criteria.

Does Insta-Footing work on an existing slab without a new concrete footing?

Within Nolan’s documented interior application, the steel plate distributes the design load through the existing slab and into the compacted support beneath it. The analyzed capacities come from that combined plate-slab-soil load path.

This does not mean every basement slab can replace a project-specific footing. The design requires the stated slab thickness and strength, tight compacted support, minimum soil bearing, edge distance, concentric load, and project load.

If any condition differs, the standard report does not establish capacity for the project.

What anchorage is required?

The design report identifies three anchorage systems: ½-inch expansion anchors, concrete screws, and powder-driven fasteners. The project documents must select the permitted system for the specific application; the three systems are not interchangeable defaults.

Use the plate holes appropriate for the selected system. Install the selected anchors or fasteners in the locations required by the project documents and follow the anchor or fastener manufacturer’s requirements for hole diameter, embedment, cleaning, installation, edge clearances, tightening, and inspection.

What is the installation sequence?

Nolan’s current instructions give six steps:

1. Verify the location. Confirm plate and post size, design load, slab thickness and strength, soil support, 7-inch edge distance, anchor clearances, and embedded utilities.
2. Support and prepare. Temporarily support and unload the post area under the project plan. Remove coatings, debris, and irregular material so the bearing surface is level, sound, and capable of full contact.
3. Position the plate. Place it flat on the slab, center the post location, square the connector to the framing above, and recheck clearances.
4. Prepare the selected anchorage. Use the plate holes required for the project-selected ½-inch expansion anchors, concrete screws, or powder-driven fasteners. Follow the system manufacturer’s drilling, cleaning, embedment, and installation requirements where applicable.
5. Anchor and set the post. Install the permitted anchorage in the locations required by the project documents and verify it as specified by the manufacturer. Set the specified post plumb and centered, then secure it under the connector details.
6. Transfer load and inspect. Confirm full bearing, anchor seating, post alignment, and connector engagement. Transfer load gradually and remove temporary support only when authorized.

This is not a general temporary-shoring design. The equipment, layout, unloading method, and load-transfer plan must come from the project design.

What should the final inspection confirm?

Before the installation is accepted, verify:

• Plate size, post size, and design load match the design selection.
• The slab is level, sound, at least 3½ inches thick, and at least 2,500 psi.
• Compacted support and 2,000 psf allowable soil bearing were verified.
• The plate is at least 7 inches from every slab edge.
• The plate bears fully and evenly on the concrete.
• The project-selected anchorage is properly installed and verified under the manufacturer’s requirements.
• The specified post is centered, plumb, and secured under the connector details.
• Load transfer caused no movement, cracking, or settlement.

Record the project, installer, date, plate and post size, design load, and report number.

When must work stop?

Stop and contact the engineer if:

• The slab or supporting material cannot be verified.
• The slab is cracked, deteriorated, settled, or uneven.
• The minimum edge distance cannot be achieved.
• The project load exceeds the selected capacity.
• Full plate bearing cannot be achieved.
• The specified post cannot be centered and secured under the connector details.
• The required anchorage and connector details cannot be achieved.
• The proposed environment, slab condition, post configuration, or load falls outside the governing report and project design.

Do not solve those conflicts by changing anchors, moving the post, selecting a larger plate, or modifying the connector without design documentation. When leveling is required, use non-shrink grout only where an approved leveling detail permits it.

FAQ

One last thing

Do not start with the plate size. Start with the design load and existing slab-support system, then verify the analyzed pairing or alternate post design, plate, edge distance, anchorage, connector, and installation sequence.