Around the perimeter of the building, a specialty subcontractor installed helical piers as close to the foundation walls as practical. Given the region's expansive clay soils, the lead helix was driven to a depth of around 30 feet.
The pier contractor then cut the tops of the extension shafts to a uniform height and welded on a steel plate fitted with rebar dowels.
Each pier was topped with a steel-reinforced concrete pier; a steel bearing plate was embedded in the wet concrete at exact finish height.
LVL ledgers attached to the exterior wall studs with structural screws provided a means of support as the sill was removed and the steel beam maneuvered into place.
Emplacement of the steel beam
At the center bearing wall, the crew had to work around the temporary supports under the short joist remnants as the steel was inserted.
To make this process easier, the beam was fabricated in sections designed to be bolted together on site.
Working a wall section at a time, the crew cut the studs off and extended them to the new girder under the bearing wall.
Along the outside walls, a double rim was installed from outside at the same elevation as the original sill.
Upside-down joist hangers help transfer roof loads to the new steel beam.
A heavy vapor retarder will help keep the crawlspace dry.