Cladosporium species in Illinois homes
The most common mold on earth, indoors and out
What this species signals about a building
Cladosporium dominates outdoor air in most climates, so its indoor presence is expected at background levels. The signal is pattern: concentrated growth on condensation surfaces — windows, registers, cold corners — points to humidity and thermal-bridge issues rather than bulk leaks.
Where Illinois buildings feed it
Humid continental with cold winters and humid summers. Basement-dominant stock; summer condensation on cool foundation walls behind finished basement framing is the leading hidden pattern.
Read those two paragraphs together and the assessment map draws itself: this organism grows where its moisture requirement is met, and Illinois'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
Surface cleaning plus environmental correction: improve ventilation, address thermal bridging and window condensation, and control humidity. Recurring growth after cleaning means the condensation driver was not fixed.
Olive-green to brown-black colonies with a suede-like texture, common on surfaces as spotty growth rather than large mats.
- Basement seepage and summer basement condensation
- Ice damming
- Freeze-thaw plumbing failures
Illinois questions
Where does Cladosporium species typically show up in Illinois homes?
The organism's requirements don't change by state — it grows where its moisture threshold is met. What changes is where Illinois buildings meet that threshold: basement seepage and summer basement condensation Combined with the local housing stock (basement-dominant stock; summer condensation on cool foundation walls behind finished basement framing is the leading hidden pattern), that's where an assessment should look first.
Does finding Cladosporium species mean something different in IL?
As a predominantly outdoor genus, Cladosporium contributes to the outdoor-species side of indices like ERMI. Elevated indoor growth matters more as a humidity diagnostic than as a water-damage marker, though heavy indoor amplification is still a condition to correct. In Illinois, 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 Cladosporium species contamination in Illinois?
Remediation requirements are set by the contamination, not the species name: surface cleaning plus environmental correction: improve ventilation, address thermal bridging and window condensation, and control humidity. We match Illinois households with providers vetted on containment discipline, fine-particle competence, and independent verification — matching is free for households.
FULL SPECIES FILE → Cladosporium species · DUST TESTING IN IL → ERMI & HERTSMI-2 in Illinois
THIS SPECIES IN OTHER PRIORITY MARKETS → California · Colorado · Florida · Nevada · Texas
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