The School District Wants a Number, Not a Plan
A school district asks you to design remediation for a 1970s elementary school with reported 'mold issues.' Walkthrough finds: ceiling tiles with water staining in two classrooms, a rooftop unit with standing water in the drain pan and biological growth on the coil, carpet in one classroom with a history of a roof leak, and a gymnasium with high humidity and condensation on windows. The district's draft scope says: 'HEPA vacuum all rooms, fog with an antimicrobial, replace stained tiles, retest air.' Budget is fixed and tight; summer break is 10 weeks. The district wants the scope finalized in one meeting and asks you to 'just add the clearance numbers.'
1. Critique the draft scope and identify what it omits.
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The draft scope treats symptoms, not causes.
Problems:
- No moisture source correction. The roof leak, the RTU drain pan, and gym condensation are the drivers; without fixing them, remediation fails and recurs.
- Fogging with an antimicrobial is not a remediation method for building materials; it does not remove reservoirs, can introduce irritants, and is not a substitute for source removal.
- 'Replace stained tiles' without addressing the wetted plenum/above-ceiling surfaces may leave contamination behind.
- 'Retest air' with no criteria is a number without a decision rule.
- Carpet with a leak history is a porous reservoir; it needs assessment for removal, not just vacuuming.
Omissions:
- HVAC assessment and correction (drain pan, coil cleaning, drainage, humidity control in the gym).
- Defined remediation boundaries and containment.
- Moisture verification and a clearance protocol tied to criteria.
- Sequencing within the 10-week window and a budget that reflects source correction, not just cleaning.
2. Propose a phased plan that fits the budget and schedule, and specify clearance criteria.
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Phased plan (prioritized by risk and cause):
Phase 1 - Source correction (weeks 1-3): repair roof leak; correct RTU drain pan and drainage; clean coil and pan; address gym humidity (ventilation/dehumidification, window condensation control). No amount of cleaning survives an uncorrected source.
Phase 2 - Removal and cleaning (weeks 3-6): remove and replace water-damaged ceiling tiles and any wetted above-ceiling materials within defined boundaries; assess and likely remove the leak-affected carpet; HEPA-vacuum and damp-wipe affected surfaces; contain work areas to protect occupied spaces.
Phase 3 - Verification (weeks 6-8): moisture verification of remaining assemblies against targets; visual inspection for residue; targeted surface/air sampling only where the scope requires, paired and against pre-agreed criteria.
Clearance criteria (set now, in writing): no visible contamination or residue; confirmed dry materials at defined moisture targets; HVAC functioning and drain pan dry; humidity in the gym within target; any sampling at or near outdoor/background with a defined decision rule.
Budget note: if the fixed budget cannot cover Phase 1, say so - cleaning without source correction is money wasted and will recur.
3. The district pushes back: 'Just give us the clearance numbers so we can close this out.' Respond.
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Explain that clearance numbers are the last step and only mean something against a defined scope and criteria.
- A number without a decision rule, method, and paired comparison is not clearance; it is data that can be misread.
- The durable outcome is source correction + removal + verified dryness, not a passing sample.
- Offer to provide a written clearance protocol now (methods, locations, criteria, decision rules) so the district knows exactly what 'done' means before work starts.
- Be clear about the risk of skipping Phase 1: recurrence, re-spend, and occupant complaints next year.
Close with a concrete deliverable: a scope and clearance protocol they can approve today, with the sampling plan embedded, so the meeting produces a defensible plan rather than a number.