Prevention • Dec 15, 2025 • 9 min read
Mold prevention for renters: a practical humidity checklist
This guide focuses on prevention and home comfort. It does not provide medical advice.
Important: These guides focus on low-risk, reversible steps. If your lease forbids a modification (or the task involves gas/electrical/structural work), stop and contact maintenance.
Know your target humidity
As a practical target, aim for 30–50% relative humidity indoors. Use an inexpensive hygrometer to measure.
Daily/weekly habits that work
| Area | Habit | Why it helps |
|---|---|---|
| Bathroom | Run fan during + 20 min after showers | Removes moisture before it settles |
| Shower | Squeegee walls (30 seconds) | Less water = less evaporation |
| Closets | Leave a small gap for airflow | Stagnant air traps moisture |
| Kitchen | Use range hood when boiling | Cooking is a major moisture source |
Quick renter-friendly improvements
- Clean the bathroom fan cover (dust reduces airflow).
- Address drafts that create cold surfaces where condensation forms (see window draft fixes).
- Use a dehumidifier if allowed and needed—empty it regularly.
When it's a landlord problem
- Visible water intrusion, recurring wet walls/ceilings, or peeling paint that returns.
- Persistent mold growth on porous materials.
- Ventilation fans that don't work.
Start here: Renter maintenance checklist