Installed by hand beneath an exposed foundation, this affordable approach to foundation support works best at sites with shallow bedrock or boulders and a narrow contamination zone. 2 diameter jack piles can be spaced as closely as required to accommodate foundation irregularities and they are typically left in place inside the replacement foundation as it is formed and poured. Spans exceeding 3? are not advisable, therefore where undermining an entire wall, work will typically involve two to four or more segments. Jack post piles will accommodate the pneumatic or hydraulic power assisted hand excavation with conveyors approach to cleaning up small residential sites.
As with the sectional concrete pier approach to building underpinning, jack post piles are simple and relatively lower cost, as the foundation is replaced in sections, immediately following the contamination dig out from a limited area. Where contamination has passed deeply beneath a structure, a channel is left in the foundation for conveyor placement. For this reason it is advisable to have a detailed contamination delineation plan in place before implementation. Cost for a 4? high by 6? long jack post pile segment, including foundation replacement typically runs about $5,000.