Extend Shallow Footings with Foundation Underpinning
Footings that were never deep enough, never wide enough, or never built for today's load settle and crack. Detroit Concrete extends them downward or outward in engineered bays, keeping the building supported through every pour and cure cycle. Underpinning also enables basement deepening and supports new additions. Free assessment.
When the Problem Is the Footing Itself, Not the Wall
A cracked foundation wall can often be fixed by reinforcing the wall. But if the footing underneath is too shallow, too narrow, or sitting on poor soil, wall repair alone will not stop the settlement. The footing has to be extended deeper or wider, and that is underpinning.
Underpinning also solves two other common scenarios. When a homeowner wants to lower a basement floor for more headroom, the existing footing now sits above the new floor level and must be extended downward first. When an addition is planned and the structural engineer determines the existing footing cannot carry the new load, underpinning brings it to the engineered depth and width.
The method is always the same: the footing is supported in numbered bays while a deeper or wider section is poured beneath or beside it. Load transfers cleanly from the old footing to the new one, and the building never settles during the work. This integrates with foundation installation for new work and basement renovation projects. When cracking is only in the wall, crack repair may be the answer instead.
Recent work
The sequence
How Underpinning Gets Done in Detroit
Structural engineer designs the plan
The engineer specifies footing depth, width, materials, and the exact bay sequence so the building stays supported as each section is excavated and poured. This engineered detail is the foundation of safe underpinning.
Excavate the first bay
The first bay in the sequence is dug out to the engineered depth, never adjacent bays at once. The rest of the footing holds the load while this section is open.
Form, reinforce, and pour concrete
The new footing section is formed, rebar is placed, and concrete is poured to the engineered detail. The new concrete is pinned to the existing footing above so load transfers without gaps.
Cure and move to the next bay
The concrete cures fully before the next bay is excavated. The cycle repeats until every section of the footing has been extended to the new depth or width.
Why the bay method is essential
Bays Prevent Settlement During Underpinning Work
It would be faster to excavate the entire footing and pour a new one, but the building would collapse. Bays are the safety mechanism. Only a small percentage of the footing is unsupported at any time, and the rest is bearing the full load of the house above.
The engineered sequence also prevents mistakes. Skipping ahead, opening two adjacent bays, or pouring without proper curing time can cause settlement during the work itself. We follow the sequence exactly as designed, and we pair the work with foundation waterproofing on newly exposed wall sections before backfill to keep groundwater out.
Bay sequence, basement deepening, additions and when underpinning is the right tool.
If settlement keeps happening after repair attempts, if the cracking is at the footing rather than just in the wall, if the soil bearing capacity has changed, or if you are adding load or lowering the basement floor. The assessment will tell us which is right.
Yes. The bay sequence means only a small section of footing is unsupported at any time, and the rest is bearing the load. Most homeowners stay in their homes through underpinning; we let you know if your situation is the exception.
Yes, that is one of the main uses. Lowering a basement floor below the existing footing requires the footing to be extended downward in bays; once underpinned, the floor can be excavated to the new depth and a new slab poured.
Only when the new load on the existing footing exceeds what the footing was sized for. The structural engineer for the addition determines that; we underpin the existing footing to the engineered detail when required.
Several weeks for a typical residential underpinning, because each bay has to be excavated, formed, poured and cured before the next bay starts. The full schedule is in the written quote so you can plan around it.
Homeowner reviews
What Detroit Homeowners Say About Their Underpinning Projects
We added a second storey and the engineer said underpin. Detroit Concrete did the sequence by the book, addition went on top, no settlement since. Done right.
T. J.
Detroit
★★★★★
Settlement that two other contractors had tried to fix as wall cracks was actually a footing problem. Underpinning solved it. Cracks haven't moved since.
N. K.
Warren
★★★★★
Basement deepening project, underpinning first, then the new lower slab. Headroom we wanted, structure stronger than before. Worth every cent.
U. O.
Dearborn
★★★★★
Engineered, sequenced, communicated every step. Lived in the house through the whole project, never felt unsafe. Underpinning is a craft and these guys know it.
G. H.
Sterling Heights
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Describe what is happening with the foundation, whether it is settlement, an addition, or basement deepening, and we will assess it at no charge and provide a written quote with timeline.
