Mold Remediation Calculator

This calculator prices HVAC-system mold at roughly $30 per square foot, twice the roughly $15/sqft for surface mold and noticeably more than the roughly $22/sqft for structural mold behind walls or framing. HVAC contamination is harder and more specialized to remediate -- ductwork often has to be professionally cleaned or partially replaced, and because the system actively moves air, mold there has a higher chance of having spread spores throughout the building before it was caught.

Containment cost combines a fixed base amount tied to the selected level -- roughly $500 for a small/basic setup, $2,000 for a medium full-containment setup, or $4,500 for large-scale full HEPA containment -- plus an additional $1.50 per affected square foot on top of that base. On a large job, the base amount alone can represent a meaningful share of total project cost even before remediation and testing are added.

No -- affected square footage scales remediation cost directly (rate per square foot times area) and adds a smaller per-square-foot component to both testing and containment cost, but testing and containment also carry fixed base costs (a flat testing base and a containment-level base amount) that don't grow with area at all. That means small jobs pay a larger share of total cost as fixed overhead, while very large jobs are increasingly dominated by the per-square-foot remediation rate.

Clearance testing -- a second round of air sampling after remediation is complete -- verifies that spore counts in the treated area have actually returned to acceptable levels, since mold can be invisible to the eye at concentrations that still pose a health risk. This calculator's testing cost line item already assumes two rounds of sampling (pre- and post-remediation) rather than a single inspection, budgeting for that verification step from the start.