Testing & Meters
Best Hygrometer: Why Accuracy Matters and How the Salt Test Proves It
A good digital hygrometer costs $10–30 and should read within ±2–3% RH; bargain units drift ±5% or worse. The number that decides whether yours is hon…
Mold test kits, moisture meters and hygrometers: how they work, what they miss, and the honest $15 kit vs $300 lab comparison.
A good digital hygrometer costs $10–30 and should read within ±2–3% RH; bargain units drift ±5% or worse. The number that decides whether yours is hon…
A pin meter ($20–50) jabs two probes into the material and reads absolute moisture content — best for bare wood, where you want a real number and a co…
A DIY mold test kit runs $15–50 and is worth buying for exactly one purpose — confirming that a specific suspicious spot is biological growth. It is n…
A DIY petri kit is a shallow dish of nutrient agar that catches whatever spores drift onto it, then feeds them until colonies grow large enough to see…
Testing is the last step, not the first. Work in order: use your nose, then your eyes, then a moisture meter to find where water is or was, then decid…
A $15–50 kit answers "is this specific spot mold?" A $300–500 inspection answers "where is my hidden moisture, how far has it spread, and what's drivi…
Aim for 30–50% relative humidity, and never let it sit above 60% — that's the EPA-aligned range. But it shifts with the season: in winter, target 30–4…