the problem is that tax law changes effective for the years 2018-2025 bar personal casualty losses unless attributable to a federally declared disaster. (an exception if there are casualty gains then casualty losses can be used to offset them) also see PUB 547https://www.irs.gov/pub/irs-pdf/p547.pdf
thus deteriorating foundations that would have qualified Qualified disaster loss. A qualified disaster
loss is an individual’s casualty or theft loss of
personal-use property that is attributable to a
major disaster declared by the President under
section 401 of the Stafford Act in 2016, as well
as from Hurricane Harvey, Tropical Storm
Harvey, Hurricane Irma, Hurricane Maria, or
from the California wildfires in 2017 and
January 2018.
A qualified disaster loss is now expanded to
include an individual’s casualty and theft of
personal-use property that is attributable to a
major disaster that was declared before
February 19, 2020, by the President under
section 401 of the Stafford Act and that
occurred in 2018 and before December 21,
2019, and continued no later than January 19,
2020. However, this change does not include
those losses attributable to California wildfires
in January 2018 (which received special relief in
2018).
thus losses from crumbling foundations are not deductible for 2018-2025
