A shed pier foundation supports a building at specific locations rather than across a continuous concrete slab. In a suitable design, the piers carry beams, runners, or other structural members beneath the shed.
This approach may be worth considering when a project calls for individual footings or an elevated floor. However, choosing a few convenient positions and pouring concrete into holes is not enough to establish a reliable foundation.
The pier layout must work with the shed’s floor design, ground conditions, loads, and connections.
This guide explains the information to obtain before construction. It focuses on concrete piers; ground screws and helical piles are different systems with their own design and installation requirements.
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Still choosing your shed? Explore My Shed Plans. Check the floor and foundation information for your preferred design before deciding whether concrete piers are appropriate.
What Is a Shed Pier Foundation?
A concrete pier is an individual support that transfers load from the building toward suitable supporting ground.
Depending on the design, a pier may connect directly to a runner or beam, or support a post beneath the floor. Some arrangements also include a wider footing at the bottom.
The important point is how the parts work together.
| Component | Its role in the foundation |
|---|---|
| Floor framing | Carries the floor and its intended loads |
| Beams or runners, where specified | Transfer loads to designated supports |
| Posts, where specified | Connect elevated framing to the pier arrangement |
| Connections | Transfer the forces required by the design |
| Concrete piers and footings | Transfer loads into the supporting ground |
Not every shed uses all these components.
Start with the actual design rather than assembling a foundation from unrelated examples.
When Might Concrete Piers Be Suitable?
Piers are an option to discuss when:
- The selected shed design calls for individual supports.
- The project requires footing details that a surface pad alone does not provide.
- The floor needs to be elevated.
- Site conditions make a designed pier arrangement worth comparing with other foundations.
A sloping site may be a reason to investigate piers, but it does not automatically make them the best solution.
Similarly, a shed with a built-in floor is not necessarily designed to sit on a few isolated supports. Its manufacturer may require a different bearing arrangement.
Our shed foundation options guide compares piers with other approaches.
Start With the Floor Plan and Support Layout
The floor and foundation need to be designed together.
Before discussing pier locations, obtain drawings showing the floor framing, beams or runners, openings, and intended loads.
Ask the provider:
- Which members bear on the piers?
- Where are the required support points?
- What spans are permitted between supports?
- Are there concentrated loads to consider?
- How are the members connected?
- Does the design require bracing?
A support placed in the wrong location may not carry the member it was intended to support.
Our upcoming shed floor framing guide explains how to identify the main parts of the floor system.
How Many Piers Does a Shed Need?
There is no dependable pier count based only on the shed’s width and length.
Two sheds with the same footprint may use different framing, spans, materials, and load assumptions. Those differences can change the required support arrangement.
Do not treat an online statement such as “six piers for a small shed” as a specification for your building.
Obtain a dimensioned layout showing every pier location and the member above it.
Why More Piers Are Not Automatically a Complete Fix
Adding supports does not resolve an unclear design by itself.
The supports still need suitable bearing, correct heights, appropriate connections, and a coordinated arrangement with the framing.
If you want to change the specified layout, have the change reviewed before excavation.
What Determines Pier Depth and Size?
Pier dimensions depend on more than the concrete form available at the store.
The design needs to account for factors such as:
- Loads transferred at each support.
- Supporting ground conditions.
- Required bearing area.
- Local frost considerations.
- Pier height above ground.
- Lateral and uplift forces.
- Applicable project requirements.
A foundation contractor’s standard dimensions may describe its typical work, but they are not automatically suitable for every property.
Ask for the actual specifications for your shed.
Frost Depth Is One Part of the Question
Where frost protection is required, confirm the applicable foundation detail with the responsible designer and local authority.
Do not choose a depth solely from a broad climate map or a neighboring project.
Reaching a particular depth does not answer every question about soil bearing, pier dimensions, reinforcement, or connections.
For the local-approval questions, see do I need a permit for a shed?.
Plan the Height Above Ground
Pier height affects more than the appearance of the finished shed.
It influences the floor elevation, entrance, connections, and—where posts are used—the stability requirements of the supporting structure.
Before finalizing the height, check:
- The doorway threshold.
- Space for a suitable ramp or step.
- Access for maintenance.
- The slope beneath the building.
- Required clearances in the selected design.
- How the structure resists sideways movement.
Avoid turning a low foundation detail into a tall raised platform without design review.
A bracket that holds a post in position does not necessarily provide every form of resistance the structure needs.
Connections and Bracing Need Their Own Details
The concrete supports are only part of the system.
Obtain specifications for the connections between the piers, posts, beams, floor, and shed structure, as applicable.
For each connector, identify:
- The exact product or approved specification.
- Required anchors.
- Specified fasteners.
- Installation orientation.
- Concrete and timber requirements.
- Relevant installation limits.
Simpson Strong-Tie’s guidance distinguishes ordinary post bases from products specifically designed to resist rotation. That illustrates why connectors should be selected for the required forces rather than by appearance.
Our upcoming guide to how to anchor a shed explains how to review the complete restraint arrangement.
Want to understand the support system before ordering materials? Take a look at My Shed Plans. Review the selected design’s foundation and floor drawings, and clarify any missing connection or support details.
Can Piers Be Combined With a Gravel Pad?
Yes, some foundation systems combine concrete piers with a prepared gravel area.
The components may serve different purposes: designated concrete supports can carry specified loads while the aggregate provides the planned surface beneath and around the building.
However, the relationship between them must be clear.
Ask whether the shed bears on the piers, the aggregate, or a coordinated combination. Do not create a mixed support arrangement by guesswork.
See our gravel shed foundation guide for the material and preparation questions associated with that part of the project.
Installation Planning: What Happens Before the Pour?
The following sequence is a planning overview, not a substitute for the foundation drawings.
1. Confirm the Design and Required Reviews
Have the shed dimensions, support layout, pier details, and connection information ready.
Confirm the applicable approval and inspection sequence before starting.
2. Complete Site and Utility Checks
Assess access, slope, drainage, and the proposed excavation locations.
Arrange utility locating before digging, including separate checks for private services where needed.
Our guide to preparing ground for a shed covers the preliminary work.
3. Establish Reference Lines and Levels
Use the dimensioned layout to mark the supports accurately.
Retain reference points that will remain usable during excavation and placement. The contractor should have a clear method for checking locations and finished elevations.
4. Excavate and Verify Conditions
Follow the specified dimensions and preparation method.
If excavation reveals unexpected fill, water, obstructions, or unsuitable ground, resolve the condition before pouring.
Do not assume the original detail remains appropriate after the site reveals something different.
5. Prepare Forms, Reinforcement, and Connections
Install the specified components and arrange required inspections before they are concealed.
Coordinate cast-in hardware positions with the framing above.
6. Place, Cure, and Check the Concrete
Follow the concrete specification and curing requirements.
Confirm when framing and anchoring work may begin. Concrete that looks dry is not automatically ready for the intended loading.
Our concrete shed foundation guide explains the broader planning questions around concrete work.
What Should a Pier Foundation Quote Include?
Ask for a quotation tied to the same drawings and site information you will use for construction.
Check whether it includes:
- Layout and elevation checks.
- Excavation and spoil removal.
- Footings and pier forms.
- Reinforcement where specified.
- Concrete and delivery.
- Cast-in hardware.
- Curing and protection.
- Required inspections.
- Posts, beams, or connections above the piers.
- Cleanup and site restoration.
Clarify whether the contractor is delivering completed concrete supports only or the entire foundation and floor-support system.
Include all parts in your shed-building budget.
A quote for bare piers cannot be compared directly with one that includes beams, connections, and associated work.
Common Mistakes to Avoid
Choosing Pier Locations Before Reviewing the Floor
The supports must match the framing they carry.
Copying Dimensions From Another Project
A different site or load arrangement may require different details.
Treating Every Post Base as Equivalent
Connections have specific functions, capacities, and installation requirements.
Ignoring the Raised Entrance
Check the ramp or step arrangement before finalizing elevations.
Leaving Drainage Unresolved
Individual supports do not remove the need to manage water around the site.
Starting Framing Without Confirming Readiness
Coordinate concrete curing, anchor requirements, and construction loading.
Frequently Asked Questions
How far apart should shed foundation piers be?
Use the spacing in the foundation and floor design. The correct layout depends on the supported members, loads, and ground conditions.
Are piers better than concrete blocks?
They are different systems. Designed piers may address requirements that surface blocks do not, but the right choice depends on the project. Our shed foundation blocks guide explains that alternative.
Can a beginner install a pier foundation?
Some work may be manageable with appropriate instruction, equipment, and a complete design. Excavation conditions, layout accuracy, concrete work, and inspections can make professional assistance worthwhile.
Do all piers need reinforcement?
The design determines the requirement. Do not omit or add reinforcement as a substitute for obtaining the correct specification.
Can I use piers beneath a prefabricated shed?
Only if the shed provider accepts the support arrangement. Confirm the required bearing locations and connection details before construction.
Are piers suitable for a sloping yard?
They may be an option, but the slope, ground conditions, exposed support height, and stability requirements need assessment.
Do I need a separate anchoring system?
The design must provide the required restraint through appropriate connections. Whether that uses the pier connections or additional components depends on the complete system.
Design the Supports as Part of the Shed
A pier foundation works through its relationship with the floor, connections, and supporting ground.
Obtain the layout and specifications before digging. Coordinate elevations, access, hardware, and inspections so the foundation is ready for the building it must support.
Visit Beginner Shed Guide for more help organizing your project.
Ready to review a shed design and its foundation needs? Explore My Shed Plans, check the available samples, and confirm the support requirements for your preferred shed.
Resources
- Site Prep: Concrete Pier Installation — A contractor’s overview of factors affecting pier dimensions and depth.
- Site Prep: Shed Foundation Piers — Examples of pier arrangements; project-specific details still need confirmation.
- Simpson Strong-Tie: Post Bases — Product information for specified post connections.
- Simpson Strong-Tie: Understanding Post Cap Lateral Capacities — Technical discussion illustrating why connection functions matter.
- Your foundation designer, shed provider, and local authority — Confirm requirements for the actual project.
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Building disclaimer: This article provides general planning information, not pier dimensions, spacing, load capacities, or a site-specific foundation design. Follow the selected design, applicable requirements, and product instructions. Obtain qualified assistance for uncertain ground or structural details.