Basement Wall Replacement in Ann Arbor

A single wall that has pushed in can be rebuilt without touching the other three. The crew digs a trench along that side down to the footing, sets temporary beams and posts inside to carry the floor joists, and takes the block down course by course. With the footing exposed, they check it for cracks and level before laying anything new.

The new wall goes up in concrete masonry units with steel bars set in the cores and grout poured around them. Michigan's code points masonry foundation walls to its masonry chapter, which calls for hollow units bedded in mortar across the full face shell and grout to ASTM C476 or a pourable Type M or S mortar. One rule matters for scheduling: backfill can't go against the new wall until it is anchored to the floor above or braced, except where it holds back less than 4 feet of soil. So the trench stays open for a while, and it should be fenced.

Sometimes only the upper part of a wall has moved: the top few courses have rolled inward under the sill while the lower wall stands plumb. Here the crew supports the house, removes those courses, and relays them with the sill plate re-anchored to the new block. The dig is shallower, and the job is smaller.

It's also the moment to check the wall's height above the soil. Michigan's code wants foundation walls to stand at least 6 inches above finished grade, or 4 inches where there's masonry veneer. Over the decades, mulch beds and topsoil creep up against older houses until the siding and sill sit almost at ground level. A rebuild of the top courses can bring that margin back, together with regrading.

A failed wall can also be replaced with poured concrete instead of block. Forms go up on the footing, rebar is tied to the sizes in the code's tables, and the concrete must reach at least 2,500 psi at 28 days, the code's minimum outside the high seismic categories. The code also requires the wall to be laterally supported at the top and bottom, which is why the connection to the floor framing gets as much attention as the pour.

Before backfill, the outside face is dampproofed from the footing to finished grade. Where the water table is high, the code calls for waterproofing instead, with options such as 40-mil polymer-modified asphalt or 6-mil polyethylene. Our view: in wet clay, ask which of the two the estimate assumes, because they're not the same product or price. The drain beside the footing is covered on the basement leak repair page.

When every wall has failed, or a fieldstone foundation is crumbling all the way around, the house can be raised on steel beams and cribbing while a new foundation goes in underneath. New footings have to reach Michigan's frost depth (see helical piers for decks and additions for the rule), the new walls go up, and the house is set back down and tied to them. The lift itself is described on the house leveling page.

This is the most expensive foundation job there is. HomeGuide puts house lifting with foundation replacement at $20,000 to $100,000 nationally, against $10,000 to $40,000 for lifting alone (February 2026).