SPECIES FILE · AUREOBASIDIUM PULLULANS · IA

Aureobasidium pullulans in Iowa 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 Iowa buildings feed it

Humid continental with humid summers and severe winters. Basement-heavy stock in flood-prone river basins; sump and drainage systems are front-line defenses.

Read those two paragraphs together and the assessment map draws itself: this organism grows where its moisture requirement is met, and Iowa'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.

IA MOISTURE DRIVERS
  • Basement seepage and high water tables
  • Spring flood events
  • Summer basement condensation
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.

Iowa questions

Where does Aureobasidium pullulans typically show up in Iowa homes?

The organism's requirements don't change by state — it grows where its moisture threshold is met. What changes is where Iowa buildings meet that threshold: basement seepage and high water tables Combined with the local housing stock (basement-heavy stock in flood-prone river basins; sump and drainage systems are front-line defenses), that's where an assessment should look first.

Does finding Aureobasidium pullulans mean something different in IA?

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 Iowa, 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 Iowa?

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 Iowa 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 IAERMI & HERTSMI-2 in Iowa
THIS SPECIES IN OTHER PRIORITY MARKETS → California · Colorado · Florida · Nevada · Texas
NEXT SPECIES IN IAMucor and Rhizopus species in Iowa

Dealing with Aureobasidium pullulans in Iowa?

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