Understand Chicago-area common brick repair peculiarities when scoping tuckpointing or repair work on Chicago-region historic buildings

Steps

1. Recognize that a large share of Chicago and Chicago-region pre-WWII buildings (including the common two- and three-flat and bungalow building stock) used locally produced, lower-fired common brick that is notably softer and more porous than modern brick
2. Assume original construction used lime mortar unless verified otherwise, and treat any prior hard portland-cement repointing on this brick as a likely cause of visible spalling (consistent with the general hard-mortar-on-soft-brick failure mode)
3. Verify current condition and mortar type on a project-specific basis rather than relying on generalized 'Chicago brick is always X' assumptions, since building stock varies by era, original builder, and prior repair history
4. Source replacement brick and salvage from regional suppliers experienced with Chicago-common and Chicago-face brick specifically, since matching color/texture for this regional brick type is a specialized sourcing task
5. Specify a lime-based or lime-rich repointing mortar appropriate to the soft brick, following the same softer-than-masonry principle used generally for historic soft brick, rather than a regional-specific mortar recipe not grounded in the actual wall's mortar analysis
6. Where the building is in a Chicago landmark district or individually landmarked, confirm any local landmarks-commission review requirements before specifying repair materials, since local preservation review may add approval steps beyond the technical repair scope