Rising damp
Moisture rising vertically through masonry walls from the ground, in the absence of a working damp-proof course.
Rising damp differs from salt damp only in emphasis. Rising damp focuses on the water mechanism; salt damp focuses on the salts that water carries. The two terms are often used interchangeably in Adelaide inspections.
Symptoms: tide-mark stains, blown plaster, swollen architraves, rotten skirting boards, musty smell at the base of walls.
Treatment options include chemical DPC injection, physical DPC retrofit, or in some cases just improving sub-floor ventilation and drainage. Always get specialist advice before committing to a major DPC retrofit.
Salt damp
Salt-laden moisture wicking up from the ground into masonry walls. Visible as white crystalline efflorescence on lower courses, blown render, or paint flaking on internal walls.
Damp-proof course (DPC)
An impermeable layer in masonry walls that prevents moisture rising from the ground. Pre-1940s homes often lack a working DPC.