Structural Restoration SOP Example

Lally Column Replacement — Crawlspace

Shore floor, remove failed column, install new grouted lally with load transfer verification.

1. Crawlspace assessment & pre-work safetyEnter crawlspace with appropriate PPE: knee pads, hard hat, nitrile gloves, and P100 respirator for confined space with potential radon or biological hazards. Assess existing column condition — note rust, corrosion, buckling, or base plate failure. Identify existing floor deflection above using straightedge or level. Confirm no utilities (gas, plumbing, electric) run within the shoring work zone before proceeding.
2. Install temporary shoringPosition temporary shoring post within 12" of the existing column on the bearing axis — do not offset shoring perpendicular to the beam. Use a properly rated hydraulic jack (minimum 20-ton capacity for residential main girder). Place jack on a 2x8 or larger base plate to distribute load on soil. Raise jack slowly until it makes contact and begins to take load — stop before lifting the structure. Verify temporary post is plumb with level on two perpendicular faces before proceeding.
3. Remove existing columnWith shoring confirmed functional, slowly relieve load from existing column by lowering it with a pipe wrench or adjustable mechanism. Once load-free, mark base plate location on footing for reference. If column is welded to cap plate, use angle grinder to cut free. Remove column from crawlspace. Inspect existing footing surface — if cracked, spalled, or insufficient, notify project manager before proceeding.
4. Prepare footing & set new columnClean footing surface and remove all debris, rust staining, and loose concrete. Set new lally column on footing — center on footing and align with the beam above. Verify column is plumb in both axes with a 4-foot level. Confirm cap plate is in contact with beam on full bearing area. If there is any gap between cap plate and beam, use shims to achieve full bearing before grouting the base.
5. Grout base & transfer loadPack non-shrink grout beneath the base plate to ensure 100% bearing contact with the footing — leave no voids. Allow grout to reach initial set (typically 30–60 minutes per product spec) before applying load. Slowly transfer load from the hydraulic jack to the new column — raise jack 1/8" at a time over several minutes. Verify floor above does not reflect any unexpected uplift or movement. Once confirmed load-bearing, lower and remove the jack completely.
6. Remove shoring & final inspectionSlowly lower and remove temporary shoring post and base plate. Inspect column after full load transfer — verify it remains plumb and the grout has maintained contact with footing. Check floor above for any unexpected movement or cracking. Photograph completed installation showing column, cap plate contact, grouted base, and footing. Remove all tools and materials from crawlspace. Document installation with photos and note final column plumbness reading.