Older homes, additions, and basement deepening projects often require footings to go deeper or wider than they were originally built. Portland Concrete extends those footings in controlled bays, keeping the structure supported throughout the work. Each project is engineered, and we provide a free assessment.
When the Issue Is the Footing Itself, Not the Wall
A cracked foundation wall can often be fixed by reinforcing the wall. But if the root cause is a footing that was never deep enough, never wide enough, or built on poor soil, wall repair alone will not stop the movement. The footing itself must be extended or rebuilt.
Underpinning also solves the problem when you want to lower a basement floor for more headroom, or when an addition puts new weight on an existing footing that was not sized for it. In all three cases, the solution is the same: extend the footing downward or outward in a controlled sequence.
The concrete slab and the walls above depend on the footing being solid. We pair underpinning with basement floor work when needed, and we always check whether crack injection or full structural repair might be the better choice for your situation.
Recent work
The underpinning process
How We Extend a Foundation in Portland
Structural engineer designs the sequence
The engineer specifies footing depth, width, materials, and the exact order of bay excavation and pouring so the building remains supported at every stage of the work.
Excavate one bay at a time
Following the engineered sequence, we dig out one section of footing at a time, never two adjacent bays simultaneously. The rest of the footing carries the load while that bay is open.
Form and pour the new footing section
The deeper or wider footing is formed, reinforced with rebar, and poured in concrete. We allow full curing time and then tie it securely to the existing footing above.
Move to the next bay in sequence
Once the first bay is cured and load-bearing, we move to the next bay in the engineered sequence and repeat the cycle until the entire footing is extended to the new depth or width.
Why bays are essential
The Bay Sequence Is What Makes Underpinning Safe
It would be faster to dig out the entire footing and replace it, but that would leave the building unsupported and cause immediate settlement. Bays solve this by keeping most of the footing bearing load while only a small section is excavated and poured at a time.
The engineered sequence is not something we can improvise or skip steps on. Doing adjacent bays out of order, rushing the cure time, or filling without proper compaction risks settlement during the work itself. We follow the sequence exactly as designed, and we waterproof the newly exposed wall before backfilling to protect the concrete from groundwater and frost. Our waterproofing service is part of the underpinning package, and we coordinate with basement renovation work when the project includes floor lowering.
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 Portland Homeowners Say About Their Underpinning Projects
We added a second storey and the engineer said underpin. Portland Concrete did the sequence by the book, addition went on top, no settlement since. Done right.
T. J.
Portland
★★★★★
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.
Vancouver
★★★★★
Basement deepening project, underpinning first, then the new lower slab. Headroom we wanted, structure stronger than before. Worth every cent.
U. O.
Beaverton
★★★★★
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.
Gresham
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Practical reading on planning, finishes and caring for concrete in Portland.
Describe what you are seeing, settlement, cracks, or plans for an addition or basement deepening, and we will assess the footing and provide a written quote with timeline.
