The Fix-It Playbook — Indoor Humidity: The Winter Setting

The right indoor humidity in January isn't the same number as the right humidity in July — and getting it wrong in either direction causes a different kind of damage.

Inside: Step 1: Get a hygrometer, and know your target · Step 2: If you have a whole-house humidifier · Step 3: If you're using a portable humidifier · Step 4: Bath fans and kitchen exhaust matter just as much · Step 5: Watch for the signs, not just the number · Mold prevention, in one number · The honest cost comparison · When to stop and call a pro · Troubleshooting · Printable humidity checklist.

Doing it yourself: a hygrometer ($10–15); a humidifier pad replacement ($10–50) if you already have a whole-house unit.
Calling a pro: $392–768 to install a whole-house humidifier, averaging around $580.

6 pages of labeled diagrams, parts lists and real numbers — no filler, no 40-minute video. Temperatures and measurements in both Fahrenheit/Celsius and feet/meters, so it works wherever you are. Ends with a printable checklist.

Instant PDF download: print it for the garage or follow it on your phone with the parts in hand. Yours to keep, no subscription.

Need more than this one job? The Draft-Proof Kit bundles all 5 building-envelope guides — 28 pages — for $14.