shoddy construction; jerry-built project
Colloquial term likening poor-quality building work to おから (tofu lees) — looks solid but crumbles easily. Often used in news or consumer complaints about defective housing or public works.
See also: おから
That apartment building is jerry-built; there are cracks in the walls.
The shoddy construction became an issue, and the contractor was sued.
Compound of おから (tofu lees, which are crumbly and lack substance) and 工事 (construction). The exact origin is uncertain, but it is a metaphorical coinage from the late 20th century, popularized in media reports on building scandals.