A typical job runs 1 to 2 weeks once drilling begins; sites requiring karst void confirmation or treatment can take longer.
Micropiles are small-diameter, drilled and grouted foundation elements, typically 5 to 12 inches across, reinforced with a steel bar or pipe casing and installed to depths of 50 feet or more. Instead of spreading load across a shallow footing, a micropile carries it to a deeper, confirmed bearing layer, whether that's dense soil, rock, or a zone verified clear of karst voids.
In San Antonio, that verification step matters more than in most cities, since Edwards Limestone karst and Blackland clay shrink-swell can occur within feet of each other along the Balcones Fault Zone. Because micropile rigs are compact, they can also work on tight lots near downtown and the medical center where larger foundation equipment can't maneuver. GSI's San Antonio micropile work typically centers on:
A typical job runs 1 to 2 weeks once drilling begins; sites requiring karst void confirmation or treatment can take longer.
Cost depends on pile depth, diameter, and how many piles the load requires, including any additional borings needed to confirm a void-free bearing zone.
Yes. Every design is stamped by a licensed Professional Engineer and meets IBC and Texas Building Code requirements.
GSI offers 24/7 emergency response and can typically mobilize a crew within hours of a call.
Helical piers work well in soft soil but can lose reliable capacity in the area's hard limestone or where karst voids interrupt the bearing layer. Micropiles are drilled rather than screwed in, allowing verification of the bearing zone before load is applied.
We drill test borings to confirm the bearing zone is free of voids before finalizing pile depth, rather than assuming the Edwards Limestone beneath a site is solid throughout.
Micropile drilling generates minimal vibration and a small volume of spoils compared to driven piling, making it a common choice for additions close to an existing foundation.
Yes, though we coordinate design and any required environmental protections with recharge zone requirements where a site falls within that boundary.
Every season the clay or karst beneath an under-supported San Antonio foundation keeps shifting, and repair costs climb with it. Call (855) 599-5217 to get a micropile assessment from a licensed engineer.
