Dilapidated
verb
bring into a condition of decay or partial ruin by neglect or misuse
Similar: dilapidate
verb
fall into decay or ruin
“The unoccupied house started to decay”
Similar: decay, crumble, dilapidate
adjective
in deplorable condition
“a street of bedraggled tenements”
Similar: bedraggled, derelict, ramshackle, tatterdemalion