Q: We had a new roof installed last September. It rained during construction and the roofers covered the exposed areas of the roof incorrectly so the rain came directly into the kitchen. The problem wasn't fixed immediately and mold grew. The roofer has since addressed the situation by hiring a certified industrial hygienist (CIH), dropping the ceilings, removing the affected kitchen cabinetry and remediating the mold in the house with chemicals. Results from an air test after the mold remediation showed the mold has been abated. Should the roofer install brand new cabinets instead of reinstalling the old, warped, mold-infected ones? The roofer wants to "poly" the back surface of those cabinets and reinstall them. Since mold had grown on the back side of the cabinets and the wall they were on in the kitchen, I do not want them reinstalled.

A: The ability to reutilize the moldy or water damaged kitchen cabinets depends on what materials they are made of, whether they were exposed to actual water or just high humidity, and duration of exposure. If they were on the floor and exposed to liquid water they are usually not salvageable – water-damaged particleboard will likely absorb water through the board and will often support mold growth. If the cabinets are decorative laminate covered particleboard, the water damage may also weaken the adhesive that is binding the laminate to the particleboard, and replacement would be advised.

If the cabinets are solid wood, they are more resistant to mold growth (terpenes in the wood act as an antifungal agent). Surface mold from condensation moisture can be effectively disinfected if properly treated. In some cases, the back of the cabinets can be replaced (plywood or particle board) and the fronts, if solid wood, can be reused. If solid wood is exposed to chronic water, versus a relatively short-term exposure, then wood decay can occur. From your description of the roof leak the water intrusion does not sound like it was extended over a long period of time.

The airborne mold testing that was conducted is a tool that can produce false negative data. A careful visual inspection is the most important element of any mold assessment. Mold (fungi) are living organisms and shed spores into the air as a result of environmental conditions (temperature, humidity, nutrient supply and vibration). Some fungal types have large sticky spores and do not become airborne easily. If the evaluation by the investigator relied on air sampling alone, then it was incomplete.

Thanks to Mark Goldman, who is a senior air quality scientist for Engineering and Fire Investigations (EFI), a firm that provides mold investigation and indoor air quality services nationwide. Mark can be reached at mark_goldman@efiglobal.com.

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If you have a question for a mold expert, please send it to Brett Lyon, senior editor of construction.com at brett_lyon@mcgraw-hill.com.