Mold, Moisture & Indoor Air
12 articles · A–Z master index
Air Quality
- Indoor Air Quality: Common Pollutants in Homes — The residential pollutant roster, combustion products, radon, VOCs, particulates, and biologicals, where each comes from, and the source-control-ventilation-filtration hierarchy that manages them.
- Whole-House Humidifiers: Benefits and Risks — Bypass, fan-powered, and steam humidifiers compared, the winter setpoint discipline that keeps them from feeding mold, the maintenance that keeps them clean, and who actually needs one.
Moisture
- Condensation on Windows: What It Tells You — Reading window condensation as a humidity gauge: inside, outside, and between-pane condensation each mean different things, and only one of them is the window's fault.
- Dehumidifiers: Sizing and Placement — Reading the new pint ratings, matching capacity to space and dampness, the drain-hose decision that determines whether it actually runs, placement rules, and the maintenance short list.
- Indoor Relative Humidity: Ideal Ranges by Season — The 30-to-50-percent target and why winter steps it down, what runs wrong above and below the band, the ten-dollar hygrometer habit, and the tools that move the number both directions.
- Musty Basement Smells: Finding the Source — The musty smell as moisture evidence: the suspect list from humidity and condensation to wall seepage and dead traps, the tinfoil test, and the fix ladder from dehumidifier to drainage.
- Vapor Barriers: Where They Belong and Where They Cause Trouble — What vapor barriers and retarders actually do, the climate rule that decides which side they face, the double-barrier mistake, and where air sealing matters more than vapor control.
- Water Stains on Ceilings: Reading the Evidence — What a ceiling stain's location, shape, rings, and timing reveal about its source: roof, plumbing, condensate, or shower pan, and the moisture-meter test before any repainting.
Mold
- Attic Mold: Causes and Remediation — Why attic mold is a winter condensation story, the ceiling leaks and misrouted fans that feed it, reading the north-slope pattern, remediation options, and the fix order that keeps it gone.
- Mold Basics: What Grows Where and Why — The moisture equation behind every mold problem, the common household genera and what they indicate, the surfaces mold prefers, and the cleanup-versus-professional threshold.
- Testing for Mold: When It Is Actually Worth It — Why visible mold rarely needs testing, what air and surface sampling can and cannot say, the cases where testing earns its fee, and how to buy it without buying the conflict of interest.
Ventilation
- Bathroom Ventilation: Fan Sizing and Ducting — Sizing a bath fan by CFM, the ducting rules that decide whether it works, the attic-termination sin, run-time habits and timers, and the sone ratings that determine actual use.