Are micropiles only for new buildings?
No. They can also be considered for existing structures and infrastructure. Suitability depends on project-specific loads, ground conditions, access, and the foundation connections.
Specialty structural engineering
Micropile Foundation Engineering
Micropile foundations for sites where access, existing construction, or structural loads limit other foundation options.
What affects the designRestricted accessExisting constructionGround and loads
How it works
When micropiles may fit the project
Micropiles are small-diameter drilled and grouted foundation elements that transfer structural loads into suitable ground. They can be considered for new foundations, strengthening, or support near an existing structure where access or overhead limits complicate larger equipment. Whether they fit depends on project loads, geotechnical findings, and installation constraints.
Connections to the structure are part of the foundation design. Caps, transfer beams, and existing footings must fit the new support and the construction sequence. Ground conditions, testing requirements, and the space needed for drilling are also established for the project.
Site conditions
Foundation support where drilling space is limited
Existing buildings, low overhead clearance, or narrow access can make foundation work difficult. Micropiles may offer a way to install support with smaller drilling equipment, depending on the ground, structural loads, and connections to the new or existing foundations.
- Restricted access
- Low overhead clearance, existing walls, and narrow work areas can limit the equipment available to install foundations.
- Existing construction
- Retrofit and underpinning work needs connections that transfer load from the existing structure to the new foundation support.
- Ground and loads
- The foundation must carry the structural loads using the ground conditions and design criteria established for the site.
Engineering services
Micropile layout and connections to the building
Cefali & Associates evaluates how micropiles would support the structure, including caps and connections to new or existing foundations. The design uses the geotechnical recommendations and the space available for installation.
- Feasibility
- Loads, foundation records, ground information, and access dimensions establish whether micropiles are a practical option.
- Structural connections
- Caps and other connections transfer loads between the micropiles and the structure while fitting around nearby foundation work.
- Project documents
- Drawings and calculations cover the micropiles and structural connections included in the design engagement.
We agree the drawings, calculations, and support during construction with you in the proposal.
Design considerations
Space for drilling and connections to the structure
Smaller drilling equipment may help on a restricted site, but there must also be room to connect the new piles to the structure. Foundation loads, ground conditions, existing footings, and access all affect whether micropiles are suitable.
- Loads and existing support
- Foundation records and structural loads show what the new support must carry. Existing settlement or movement may require further investigation before a foundation layout is selected.
- Ground conditions and testing
- Geotechnical recommendations inform where loads can be transferred to the ground. Capacity and testing requirements are established for the site.
- Space for drilling
- Headroom, access openings, utilities, noise limits, and sequencing affect drill selection and connection details.
Related airport work / LAX - Multiple Projects
The design in practice.
Micropiles are among the services Cefali & Associates has provided across multiple LAX projects. The wider airport portfolio includes underpinning, building shoring, approach pits, and excavation support for new construction and existing structures.
See the LAX - Multiple Projects projectRelated project work
Projects involving micropiles
See the systems, site conditions, and construction details from these projects.
Before you begin
Common questions
What should we send to discuss a micropile project?
Send structural loads and drawings, geotechnical information, existing foundation records, access limits, and the expected construction sequence.
Why are micropiles considered on limited-access sites?
Micropiles can be installed with relatively compact equipment compared with some larger drilled foundation systems. Whether they fit still depends on structural loads, geotechnical recommendations, existing foundations, overhead clearance, and the space needed to connect the piles to the structure.
How do micropiles compare with caissons or other deep foundations?
Each option has different installation space, load-transfer, and ground requirements. The practical choice comes from comparing structural loads, geotechnical recommendations, existing conditions, and construction access.
What determines the capacity of a micropile?
Capacity and testing requirements are established from the ground conditions, structural loads, and geotechnical criteria for the site.
Discuss your project
Tell us what you are planning.
Send the drawings, reports, and site information you already have, along with your schedule and the work you need help with. You do not need a complete design package to get in touch.
- Structural loads and preliminary foundation layout
- Geotechnical report and available subsurface data
- Existing footing drawings and field information, if applicable
- Access dimensions, overhead limits, and proposed construction sequence