SPECIES FILE · AUREOBASIDIUM PULLULANS · FL

Aureobasidium pullulans in Florida homes

The pink-to-black yeast-like resident of wet surfaces

What this species signals about a building

Aureobasidium thrives on repeatedly wetted non-porous and painted surfaces — the classic organism behind stubborn dark staining on caulk lines and window gaskets. It signals surface-wetting patterns: condensation, splash zones, and ventilation shortfalls.

Where Florida buildings feed it

Humid subtropical to tropical; the highest sustained moisture load in the country. Concrete-block and stucco construction hides water paths at windows and penetrations; AC sizing and envelope detailing decide whether a Florida home stays dry.

Read those two paragraphs together and the assessment map draws itself: this organism grows where its moisture requirement is met, and Florida's climate and housing stock determine where that requirement gets met most often. That intersection — not a generic national checklist — is where instruments should go first.

What remediation requires

Clean or replace colonized caulk and gaskets, then change the wetting pattern: ventilation runtime, squeegee habits in showers, and condensation control at windows. Replacing caulk without changing the moisture pattern restarts the clock.

FIELD APPEARANCE

Starts cream or pink and matures to shiny black; commonly the dark growth on bathroom caulk, window gaskets, and painted sills.

FL MOISTURE DRIVERS
  • Extreme ambient humidity most of the year
  • Hurricane and tropical-storm water intrusion
  • Oversized AC short-cycling without dehumidifying
  • Stucco and window-installation envelope failures
The lane we stay in: My Home CIRS Health provides building-science education and contractor matching. We do not diagnose, treat, or give medical advice, and nothing here replaces the guidance of a qualified physician. Your body is your doctor's domain. Your house is ours.

Florida questions

Where does Aureobasidium pullulans typically show up in Florida homes?

The organism's requirements don't change by state — it grows where its moisture threshold is met. What changes is where Florida buildings meet that threshold: extreme ambient humidity most of the year Combined with the local housing stock (concrete-block and stucco construction hides water paths at windows and penetrations; ac sizing and envelope detailing decide whether a florida home stays dry), that's where an assessment should look first.

Does finding Aureobasidium pullulans mean something different in FL?

Mostly a surface and moisture-pattern indicator rather than a hidden-reservoir marker. Persistent recurrence after cleaning is the meaningful finding — it means the wetting pattern continues. In Florida, weigh that signal against the state's dominant moisture drivers — the species tells you about the water, and the local climate tells you where that water most likely came from.

Who handles Aureobasidium pullulans contamination in Florida?

Remediation requirements are set by the contamination, not the species name: clean or replace colonized caulk and gaskets, then change the wetting pattern: ventilation runtime, squeegee habits in showers, and condensation control at windows. We match Florida households with providers vetted on containment discipline, fine-particle competence, and independent verification — matching is free for households.

FULL SPECIES FILE → Aureobasidium pullulans · DUST TESTING IN FLERMI & HERTSMI-2 in Florida
THIS SPECIES IN OTHER PRIORITY MARKETS → California · Colorado · Nevada · Texas
NEXT SPECIES IN FLMucor and Rhizopus species in Florida

Dealing with Aureobasidium pullulans in Florida?

Tell us about your house and your situation. We match you with contractors vetted on containment discipline, fine-particle competence, and willingness to be independently verified — in your area, at no cost to you.

Get matched with a vetted contractor

INDEPENDENT · NO COST TO HOMEOWNERS · NATIONWIDE