SPECIES FILE · AUREOBASIDIUM PULLULANS · ME

Aureobasidium pullulans in Maine 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 Maine buildings feed it

Cold humid continental with long winters. Very old housing stock; retrofitted insulation without air sealing creates condensation patterns the original buildings never had.

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

ME MOISTURE DRIVERS
  • Ice damming
  • Damp stone and rubble foundations
  • Winter condensation in tightened old homes
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Maine questions

Where does Aureobasidium pullulans typically show up in Maine homes?

The organism's requirements don't change by state — it grows where its moisture threshold is met. What changes is where Maine buildings meet that threshold: ice damming Combined with the local housing stock (very old housing stock; retrofitted insulation without air sealing creates condensation patterns the original buildings never had), that's where an assessment should look first.

Does finding Aureobasidium pullulans mean something different in ME?

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 Maine, 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 Maine?

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 Maine 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 MEERMI & HERTSMI-2 in Maine
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