Commercial Property Mold Due Diligence

Where Mold Fits in Due Diligence

Mold assessment usually rides alongside the property condition assessment and any environmental site assessment. It is not automatically included — a standard Phase I focuses on contamination and historical use, not indoor air quality.

If the building has flood history, deferred maintenance, or a low-slope roof near end of life, commission indoor air quality and moisture evaluation explicitly. Do not assume the PCA covers it.

What to Request From the Seller

The Tenant Complaint Log Is the Tell

The maintenance ticket history is the most underused document in commercial due diligence. Recurring tickets for the same leak, or a pattern of air quality complaints, reveals problems no walkthrough will show you.

Ask for it explicitly. Sellers who will not produce it have told you something.

Lender and Insurer Requirements

Lenders financing commercial property increasingly ask about indoor air quality where the building has known water history. Insurers may condition coverage or exclude mold entirely on buildings with prior claims.

Find out early. Discovering at the commitment stage that your lender wants an assessment, or that mold coverage is excluded, is a bad time to learn it.

Pricing the Finding

If assessment finds a problem, resist the reflex to walk. Commercial mold is usually a scoped, priceable repair. Get a licensed assessment with a written protocol, obtain remediation bids against it, and negotiate.

What you are pricing is the remediation, the moisture source repair, the rebuild, and any tenant disruption or rent abatement during the work. That last item is regularly forgotten.