Medical Office Roof Leak With Layered Flooring
At 06:40 Monday, the property manager of a 3,200 sq ft medical office suite reports a roof-drain overflow above two exam rooms and a corridor. Water entered through the ceiling grid, saturated 2x4 ceiling tiles, and ponded 3–5 mm on carpet tile over 12x12 vinyl composition tile (VCT) on slab. The leak stopped at 04:00 and was discovered at 06:00. The suite opens at 08:00 with 11 staff and 20 scheduled patients. Painted gypsum partitions show 18 in of wicking in two rooms; there is a musty odor in the corridor; temperature is 76°F and RH 63%. A non-penetrating meter reads 18–24% WME on carpet and 12–15% on VCT across about 900 sq ft; unaffected VCT reads 4–6%. Rubber cove base and plywood casework with toe kicks are present. Only one 20A circuit is available for drying equipment.
1. What water category and class of loss do you assign, and what field evidence would cause you to change either classification?
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Assign Category 2 provisionally and Class 2. Roof-drain overflow is not a potable supply line: it carries roof debris, bird droppings, and aged insulation and ceiling contact, so the water is reasonably presumed to have become contaminated before it reached the carpet and VCT. The musty odor and 6-hour discovery support that presumption, but odor alone does not prove Category 3. I would change to Category 3 only if I find sewage, toilet waste, or other black-water evidence; change to Category 1 only if the source is confirmed clean rainwater and the pathway is verified clean. Class 2 fits because roughly 900 sq ft of absorbent carpet and layered flooring are wet, gypsum wicks 18 in, and evaporation is low because carpet tile, VCT, cove base, and casework trap moisture. Class 3 would require more extensive ceiling and wall saturation or water from above into cavities; I would upgrade if ceiling cavities are wet across the suite or if water has penetrated wall cavities above 24 in. The one 20A circuit limits equipment, which affects the drying plan but not the classification.
2. Outline your inspection and evaluation sequence before placing drying equipment, including patient-safety and containment decisions.
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First confirm the roof drain is not still leaking and lock out any ceiling-grid electrical hazards. Isolate the two exam rooms and corridor with poly barriers and negative pressure if available, reschedule the 20 patients away from the work zone, and keep staff out of the wet corridor. Before equipment, complete a moisture map: thermal images of ceiling and walls, non-invasive readings on VCT and carpet, pin readings in gypsum at 6, 12, 18, and 24 in, and checks inside casework toe kicks and behind cove base. Lift several carpet tiles to see whether water is trapped between carpet and VCT; check whether VCT adhesive is intact. Remove saturated ceiling tiles and any wet insulation; bag and dispose. Document with photos and a grid sketch. Because only one 20A circuit is available, calculate amperage before placing dehumidifiers and air movers; use the circuit for the dehumidifier and run low-amp air movers on another verified circuit or arrange temporary power. Do not begin drying until the moisture boundaries and patient-safety controls are documented.
3. What documentation will you produce to support drying versus replacement of carpet tile and plywood casework?
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Produce a material-specific file: initial and final photos, moisture-map sketch, readings by material and location, psychrometric log, equipment list with serial numbers and placement, and customer authorization. For carpet tile, document whether water was Category 1 or 2, whether tiles delaminated, whether adhesive failed, and whether the backing and VCT reached the dry standard. Carpet tile is a candidate for cleaning and reinstallation only if the backing is intact, the VCT and adhesive are sound, and the material can be dried quickly; otherwise replace. For plywood casework, record pin readings in toe kicks, stiles, and shelf supports, look for swelling, delamination, and joint separation, and compare to unaffected casework. Do not rely on a single non-invasive meter reading. State the dry standard and the replacement trigger in advance, get signed scope changes, and retain daily readings. If the casework cannot be dried below the agreed wood moisture target without swelling, recommend replacement rather than repeated treatments.